A Rat Model of Rheumatoid Arthritis: TDZD-8 is Associated with the Protection Against the Induction of the Synovium Knee Joint IL-17A/GSK3β/ROS/α-SMA Axis of Fibrosis

SUMMARY: Rheumatoid arthritis (RA) that affects the synovial knee joint causes swelling of the synovial membrane and tissue damage. Interleukin-17A (IL-17A) and the enzyme glycogen synthase kinase-3β (GSK3β) are involved in the pathogenesis of RA. The link between IL-17A, GSK3β, the oxidative stress, and the profibrogenic marker alpha-smooth muscle actin (α-SMA) with and without TDZD-8, GSK3β inhibitor has not been studied before. Consequently, active immunization of rats was performed to induce RA after three weeks using collagen type II (COII) injections. The treated group received daily injection of 1 mg/kg TDZD-8 for 21 days following the immunization protocol (COII+TDZD-8). Blood and synovium tissue samples were harvested at the end of the experiment. RA development was confirmed as corroborated by a substantial increase in blood levels of the highly specific autoantibody for RA, anti-citrullinated protein antibody as well as augmentation of reactive oxidative species (ROS) levels measured as lipid peroxidation. RA induction also increased synovium tissue levels of IL-17A and the profibrogenic marker, α-SMA. All these parameters seemed to be significantly (p<0.0001) ameliorated by TDZD-8. Additionally, a significant correlation between IL-17A, ROS, and α-SMA and biomarkers of RA was observed. Thus, knee joint synovium RA induction augmented IL-17A/GSK3β/ROS/α-SMA axis mediated arthritis in a rat model of RA, which was inhibited by TDZD-8.

La artritis reumatoide (AR) que afecta la articulación sinovial de la rodilla provoca inflamación de la membrana sinovial y daño tisular. La interleucina-17A (IL-17A) y la enzima glucógeno sintasa quinasa-3β (GSK3β) están involucradas en la patogenia de la AR. No se ha estudiadol vínculo entre IL-17A, GSK3β, el estrés oxidativo y el marcador profibrogénico actina de músculo liso alfa (α-SMA) con y sin inhibidor de TDZD-8, GSK3β. En consecuencia, se realizó una inmunización activa de ratas para inducir la AR después de tres semanas usando inyecciones de colágeno tipo II (COII). El grupo tratado recibió una inyección diaria de 1 µg/ kg de TDZD-8 durante 21 días siguiendo el protocolo de inmunización (COII+TDZD-8). Se recogieron muestras de sangre y tejido sinovial al final del experimento. El desarrollo de AR se confirmó como lo corroboró el aumento sustancial en los niveles sanguíneos del autoanticuerpo altamente específico para AR, el anticuerpo antiproteína citrulinada, así como el aumento de los niveles de especies oxidativas reactivas (ROS) medidos como peroxidación lipídica. La inducción de AR también aumentó los niveles de tejido sinovial de IL-17A y el marcador profibrogénico, α-SMA. Todos estos parámetros parecían mejorar significativamente (p<0,0001) con TDZD-8. Además, se observó una correlación significativa entre IL- 17A, ROS y α-SMA y biomarcadores de AR. Por lo tanto, la inducción de AR en la sinovial de la articulación de la rodilla aumentó la artritis mediada por el eje IL-17A/GSK3β/ROS/α-SMA en un modelo de rata de AR, que fue inhibida por TDZD-8.

A rat model of rheumatoid arthritis: TDZD-8 is associated with the protection against the induction of the synovium knee joint IL-17A/GSK3beta/ROS/alpha-SMA axis of fibrosis / Un modelo de rata de artritis reumatoide: TDZD-8 está asociado con la protección contra la inducción del eje de fibrosis de la articulación sinovial de la rodilla IL-17A/GSK3ß/ROS/α-SMA

SUMMARY: Rheumatoid arthritis (RA) that affects the synovial knee joint causes swelling of the synovial membrane and tissue damage. Interleukin-17A (IL-17A) and the enzyme glycogen synthase kinase-3β (GSK3β) are involved in the pathogenesis of RA. The link between IL-17A, GSK3β, the oxidative stress, and the profibrogenic marker alpha-smooth muscle actin (α-SMA) with and without TDZD-8, GSK3β inhibitor has not been studied before. Consequently, active immunization of rats was performed to induce RA after three weeks using collagen type II (COII) injections. The treated group received daily injection of 1 mg/kg TDZD-8 for 21 days following the immunization protocol (COII+TDZD-8). Blood and synovium tissue samples were harvested at the end of the experiment. RA development was confirmed as corroborated by a substantial increase in blood levels of the highly specific autoantibody for RA, anti-citrullinated protein antibody as well as augmentation of reactive oxidative species (ROS) levels measured as lipid peroxidation. RA induction also increased synovium tissue levels of IL-17A and the profibrogenic marker, α-SMA. All these parameters seemed to be significantly (p<0.0001) ameliorated by TDZD-8. Additionally, a significant correlation between IL-17A, ROS, and α-SMA and biomarkers of RA was observed. Thus, knee joint synovium RA induction augmented IL-17A/GSK3β/ROS/α-SMA axis mediated arthritis in a rat model of RA, which was inhibited by TDZD-8.

La artritis reumatoide (AR) que afecta la articulación sinovial de la rodilla provoca inflamación de la membrana sinovial y daño tisular. La interleucina-17A (IL-17A) y la enzima glucógeno sintasa quinasa-3β (GSK3β) están involucradas en la patogenia de la AR. No se ha estudiadol vínculo entre IL-17A, GSK3β, el estrés oxidativo y el marcador profibrogénico actina de músculo liso alfa (α-SMA) con y sin inhibidor de TDZD-8, GSK3β. En consecuencia, se realizó una inmunización activa de ratas para inducir la AR después de tres semanas usando inyecciones de colágeno tipo II (COII). El grupo tratado recibió una inyección diaria de 1 µg/ kg de TDZD-8 durante 21 días siguiendo el protocolo de inmunización (COII+TDZD-8). Se recogieron muestras de sangre y tejido sinovial al final del experimento. El desarrollo de AR se confirmó como lo corroboró el aumento sustancial en los niveles sanguíneos del autoanticuerpo altamente específico para AR, el anticuerpo antiproteína citrulinada, así como el aumento de los niveles de especies oxidativas reactivas (ROS) medidos como peroxidación lipídica. La inducción de AR también aumentó los niveles de tejido sinovial de IL-17A y el marcador profibrogénico, α-SMA. Todos estos parámetros parecían mejorar significativamente (p<0,0001) con TDZD-8. Además, se observó una correlación significativa entre IL- 17A, ROS y α-SMA y biomarcadores de AR. Por lo tanto, la inducción de AR en la sinovial de la articulación de la rodilla aumentó la artritis mediada por el eje IL-17A/GSK3β/ROS/α-SMA en un modelo de rata de AR, que fue inhibida por TDZD-8.

Metformin Suppresses Thioacetamide-Induced Chronic Kidney Disease in Association with the Upregulation of AMPK and Downregulation of Oxidative Stress and Inflammation as Well as Dyslipidemia and Hypertension.

Toxic chemicals such as carbon tetrachloride and thioacetamide (TAA) are reported to induce hepato-nephrotoxicity. The potential protective outcome of the antidiabetic and pleiotropic drug metformin against TAA-induced chronic kidney disease in association with the modulation of AMP-activated protein kinase (AMPK), oxidative stress, inflammation, dyslipidemia, and systemic hypertension has not been investigated before. Therefore, 200 mg/kg TAA was injected (via the intraperitoneal route) in a model group of rats twice a week starting at week 3 for 8 weeks. The control rats were injected with the vehicle for the same period. The metformin-treated group received 200 mg/kg metformin daily for 10 weeks, beginning week 1, and received TAA injections with dosage and timing similar to those of the model group. All rats were culled at week 10. It was observed that TAA induced substantial renal injury, as demonstrated by significant kidney tissue damage and fibrosis, as well as augmented blood and kidney tissue levels of urea, creatinine, inflammation, oxidative stress, dyslipidemia, tissue inhibitor of metalloproteinases-1 (TIMP-1), and hypertension. TAA nephrotoxicity substantially inhibited the renal expression of phosphorylated AMPK. All these markers were significantly protected by metformin administration. In addition, a link between kidney fibrosis and these parameters was observed. Thus, metformin provides profound protection against TAA-induced kidney damage and fibrosis associated with the augmentation of the tissue protective enzyme AMPK and inhibition of oxidative stress, inflammation, the profibrogenic gene TIMP-1, dyslipidemia, and hypertension for a period of 10 weeks in rats.

Quercetin and resveratrol are associated with the downregulation of TNFalpha/NF-kB/inos axis-mediated acute liver injury in rats induced by paracetamol poisoning / La quercetina y el resveratrol están asociados con la regulación decreciente de la lesión hepática aguda mediada por el eje TNF-alfa/NF-kB/inos en ratas inducida por envenenamiento con paracetamol

SUMMARY: Paracetamol (known as acetaminophen, or APAP) poisoning causes acute liver damage that can lead to organ failure and death. We sought to determine that APAP overdose can augment tumor necrosis factor-alpha (TNF-α)/ nuclear factor kappa B (NF-kB)/induced nitic oxide synthase (iNOS) axis-mediated hepatotoxicity in rats, and the anti-inflammatory polyphenolic compounds, quercetin (QUR) plus resveratrol (RES) can ameliorate these parameters. Therefore, we induced acute hepatotoxicity in rats using APAP overdose (2 g/kg, orally) and the protective group of rats were treated with 50 mg/kg QUR plus 30 mg/kg RES for one week before APAP ingestion. Animals were killed at day 8. APAP poisoning caused the induction of hepatic tissue levels of TNF-α, NF-kB, and iNOS, which were significantly (p<0.05) decreased by QUR+RES. QUR+RES, also inhibited liver injury biomarkers, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Additionally, a link between liver injury and TNF-α /NF-kB / iNOS axis mediated hepatotoxicity was observed. Thus, the presented data backing the conclusion that intoxication by paracetamol increases TNF-α / NF-kB / iNOS axis -mediated hepatotoxicity, and is protected by a combination of quercetin and resveratrol.

El envenenamiento por paracetamol (conocido como acetaminofeno o APAP) causa daño hepático agudo que puede provocar una insuficiencia orgánica y la muerte. El objetivo de este trabajo fue determinar si la sobredosis de APAP puede aumentar la hepatotoxicidad mediada por el eje del factor de necrosis tumoral alfa (TNF-α)/factor nuclear kappa B (NF-kB)/óxido nítico sintasa inducida (iNOS) en ratas, y si el polifenólico antiinflamatorio compuesto por quercetina (QUR) más resveratrol (RES) pueden mejorar estos parámetros. Por lo tanto, inducimos hepatotoxicidad aguda en ratas usando una sobredosis de APAP (2 g/kg, por vía oral). El grupo protector de ratas se trató con 50 mg/ kg de QUR más 30 mg/kg de RES durante una semana antes de la ingestión de APAP. Los animales se sacrificaron el día 8. El envenenamiento con APAP en el tejido hepático provocó la inducción de niveles de TNF-α, NF-kB e iNOS, que se redujeron significativamente (p<0,05) con QUR+RES. QUR+RES, también inhibió los biomarcadores de daño hepático, la alanina aminotransferasa (ALT) y el aspartato aminotransferasa (AST). Además, se observó una relación entre la lesión hepática y la hepatotoxicidad mediada por el eje TNF-α /NF-kB/iNOS. Por lo tanto, los datos presentados respaldan la conclusión de que la intoxicación por paracetamol aumenta la hepatotoxicidad mediada por el eje TNF-α /NF-kB / iNOS, y está protegida por una combinación de quercetina y resveratrol.

Metformin ameliorates ROS-p53-collagen axis of fibrosis and dyslipidemia in type 2 diabetes mellitus-induced left ventricular injury.

BACKGROUND: The link between oxidative stress (ROS), apoptosis (p53) and fibrosis (collagen) in type 2 diabetes mellitus (T2DM)-induced cardiac injury in the presence and absence of the antidiabetic drug, metformin has not been investigated before. MATERIAL AND METHODS: T2DM was induced in rats by a combination of high carbohydrate and fat diets (HCFD) and streptozotocin (50 mg/kg) injection. The protection group started metformin (200 mg/kg) treatment 14 days prior to the induction of diabetes and continued on metformin and HCFD until being sacrificed at week 12. RESULTS: Diabetes significantly induced blood levels of ROS and left ventricular p53 and collagen expression that was inhibited by metformin. Metformin also significantly reduced glycated haemoglobin and dyslipidemia induced by diabetes. In addition, a significant correlation between ROS-p53-collagen axis and glycaemia and hyperlipidaemia was observed. CONCLUSIONS: These findings show that metformin provides substantial protection against diabetic cardiomyopathy-induced ROS-p53 mediated fibrosis and dyslipidemia.

Vitamin E protects against the modulation of TNF-α-AMPK axis and inhibits pancreas injury in a rat model of L-arginine-induced acute necrotising pancreatitis.

BACKGROUND: Acute pancreatitis (AP) associated with the modulation of TNF-α-AMPK axis in the presence and absence of vitamin E has not been investigated before. MATERIAL AND METHODS: Rats were either injected with L-arginine (2.5 gm/kg) before being sacrificed after 48 h or were pre-treated with vitamin E (60 mg/kg) and continued receiving vitamin E until the end of the experiment. RESULTS: AP was developed as demonstrated by infiltration of inflammatory cells and profound pancreas tissue damage, which were substantially protected by vitamin E. In addition, L-arginine injections significantly (p < .0001) increased the expression of TNF-α mRNA and protein, and decreased phospho-AMPK and IL-10 mRNA and protein that was significantly (p < .0001) protected by vitamin E. Furthermore, vitamin E inhibited L-arginine-induced blood levels of LDH, amylase, and myeloperoxidase. CONCLUSIONS: L-arginine-induced acute pancreatitis modulates TNF-α-AMPK axis, IL-10 and other AP biomarkers, which is protected by vitamin E; thus, may offer therapeutic potential in humans.

Metformin Is Associated with the Inhibition of Renal Artery AT1R/ET-1/iNOS Axis in a Rat Model of Diabetic Nephropathy with Suppression of Inflammation and Oxidative Stress and Kidney Injury.

Diabetes is the most common cause of end-stage renal disease, also called kidney failure. The link between the renal artery receptor angiotensin II type I (AT1R) and endothelin-1 (ET-1), involved in vasoconstriction, oxidative stress, inflammation and kidney fibrosis (collagen) in diabetes-induced nephropathy with and without metformin incorporation has not been previously studied. Diabetes (type 2) was induced in rats and another group started metformin (200 mg/kg) treatment 2 weeks prior to the induction of diabetes and continued on metformin until being culled at week 12. Diabetes significantly (p < 0.0001) modulated renal artery tissue levels of AT1R, ET-1, inducible nitric oxide synthase (iNOS), endothelial NOS (eNOS), and the advanced glycation end products that were protected by metformin. In addition, diabetes-induced inflammation, oxidative stress, hypertension, ketonuria, mesangial matrix expansion, and kidney collagen were significantly reduced by metformin. A significant correlation between the AT1R/ET-1/iNOS axis, inflammation, fibrosis and glycemia was observed. Thus, diabetes is associated with the augmentation of the renal artery AT1R/ET-1/iNOS axis as well as renal injury and hypertension while being protected by metformin.

MiR-155 Dysregulation Is Associated with the Augmentation of ROS/p53 Axis of Fibrosis in Thioacetamide-Induced Hepatotoxicity and Is Protected by Resveratrol.

Liver fibrosis is a hallmark of thioacetamide (TAA) intoxications. MicroRNAs (miRs), such as miR-155, have been implied in the pathogenesis of liver disease, and regulated by the antioxidant and anti-inflammatory compound resveratrol (RES). The link between reactive oxygen species (ROS), tumour suppressor p53 (p53), and liver fibrosis-during the pathogenesis of TAA-induced liver injury-associated with miR-155 dysregulation with and without RES incorporation has not been previously studied. Therefore, one group of rats received TAA injections of 200 mg/kg; twice a week at the beginning of week 3 for 8 weeks (TAA group; or model group), whereas the protective group was pretreated daily with RES suspension (20 mg/kg; orally) for the first two weeks and subsequently sustained on receiving both RES and TAA until being sacrificed at the 10th week. Liver injuries developed in the model group were confirmed by a significant (p < 0.0001) elevation of hepatic tissue levels of miR-155, ROS, p53, and the profibrogenic biomarkers: tissue inhibitor of metalloproteinases-1 and α-smooth muscle actin, as well as collagen deposition (fibrosis). All these parameters were significantly (p ≤ 0.0234) protected by resveratrol (RES + TAA). In addition, we observed a significant (p < 0.0001) correlation between ROS/p53 axis mediated liver fibrosis and miR-155. Thus, TAA intoxication induced miR-155 imbalance and ROS/p53-mediated liver fibrosis, with resveratrol, conversely displaying beneficial hepatic pleiotropic effects for a period of 10 weeks.

Association of resveratrol with the suppression of TNF-α/NF-kB/iNOS/HIF-1α axis-mediated fibrosis and systemic hypertension in thioacetamide-induced liver injury.

Chronic liver injury can lead to hepatic failure and the only available method of treatment would be liver transplantation. The link between inflammation (TNF-α), nuclear factor-kappa B (NF-kB), nitrosative stress (iNOS) and hypoxia-inducible factor-1α (HIF-1α) in thioacetamide (TAA) induced liver fibrosis, and hypertension with and without the incorporation of the anti-inflammatory and antioxidant resveratrol (RES) has not been investigated before. Consequently, we injected rats with either 200 mg/kg TAA for 8 weeks starting at week 2 (model group) or pretreated them before TAA injections with RES (20 mg/kg) for 2 weeks and continued them on RES and TAA until being culled at week 10 (protective group). In the model group, we documented the induction of hepatic fibrosis and upregulation of tumor necrosis factor-α (TNF-α), NF-kB, inducible nitric oxide synthase (iNOS), HIF-1α and the profibrotic biomarkers alpha-smooth muscle actin (α-SMA) and matrix metalloproteinase-9 (MMP-9) that was significantly (p ≤ 0.0014) ameliorated by RES. RES also significantly (p ≤ 0.0232) reduced triglycerides (TG), cholesterol (CHOL), very low-density lipoprotein (vLDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure, and heart rate (HR) induction by TAA. Also, a significant (p < 0.0001) positive correlation between TNF-α/NF-kB/iNOS/HIF-1α axis-mediated fibrosis and hypertension and liver injury biomarkers was observed. These findings suggest that in the hepatotoxic compound, TAA is associated with TNF-α/NF-kB/iNOS/HIF-1α-mediated fibrosis and hypertension, whilst being inhibited by RES.

Metformin Protects against Diabetic Cardiomyopathy: An Association between Desmin-Sarcomere Injury and the iNOS/mTOR/TIMP-1 Fibrosis Axis.

The intermediate filament protein desmin is essential for maintaining the structural integrity of sarcomeres, the fundamental unit of cardiac muscle. Diabetes mellitus (DM) can cause desmin to become dysregulated, following episodes of nitrosative stress, through the activation of the iNOS/mTOR/TIMP-1 pathway, thereby stimulating collagen deposition in the myocardium. In this study, type 2 diabetes mellitus (T2DM) was induced in rats. One group of animals was pre-treated with metformin (200 mg/kg) prior to diabetes induction and subsequently kept on metformin until sacrifice at week 12. Cardiac injuries developed in the diabetic rats as demonstrated by a significant (p < 0.0001) inhibition of desmin immunostaining, profound sarcomere ultrastructural alterations, substantial damage to the left ventricular tissue, collagen deposition, and abnormal ECG recordings. DM also significantly induced the cardiac expression of inducible nitric oxide synthase (iNOS), mammalian target of rapamycin (mTOR), and the profibrogenic biomarker tissue inhibitor of metalloproteinase-1 (TIMP-1). The expression of all these markers was significantly inhibited by metformin. In addition, a significant (p < 0.0001) correlation between desmin tissue levels/sarcomere damage and glycated hemoglobin, heart rate, iNOS, mTOR, and fibrosis was observed. These findings demonstrate an association between damage of the cardiac contractile unit­desmin and sarcomere­and the iNOS/mTOR/TIMP-1/collagen axis of fibrosis in T2DM-induced cardiomyopathy, with metformin exhibiting beneficial cardiovascular pleiotropic effects.

Metformin and resveratrol suppress type 2 diabetes mellitus-induced articular cartilage damage in rats associated with the inhibition of inflammation and augmentation of proteoglycans / La metformina y el resveratrol suprimen el daño del cartílago articular inducido por la diabetes mellitus tipo 2 en ratas asociado con la inhibición de la inflamación y el aumento de proteoglicanos

SUMMARY: Induction of osteoarthritis (OA) following diabetes is characterized by a sever inflammation of the joints that can lead to disability. The cartilage content of proteoglycans can substantially be reduced, following the induction of diabetes mellitus associated with inflammation as well as knee joint injury, and the antidiabetic drug metformin combined with the anti-inflammatory agent resveratrol can prevent these deleterious effects. Therefore, insulin-independent diabetes, type 2 diabetes mellitus (T2DM) was induced in Albino rats by streptozotocin (STZ) injection (50 mg/kg) after being fed on a high carbohydrate and fat diets for 2 weeks. The protective group of rats which also received a single injection of STZ was treated daily with metformin (Met; 200 mg/kg) and resveratrol (Res; 30 mg/kg) for 12 weeks. Harvested knee joint tissues were prepared for basic histology stain and for proteoglycans staining using light microscopy. Histology images showed in diabetic rats (T2DM) OA development as demonstrated by profound injury to the knee joint and severe decrease of articular cartilage proteoglycans content, which were substantialy protected by Met+Res. Met+Res also significantly (p< 0.0001) decreased diabetes induced glycemia, dyslipidemia, and the inflammatory biomarkers, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and high sensitivity C-reactive protein (hs-CRP). In addition, there was a significant correlation between OA and glycemia, dyslipidemia, and inflammation. Collectively, we demonstrate an association between knee joint damage and biomarkers of glycemia, dyslipidemia, and inflammation in diabetes-induced OA, with metformin plus resveratrol providing protective effects.

RESUMEN: La inducción de osteoartritis (OA) después de la diabetes se caracteriza por una inflamación severa de las articulaciones que puede conducir a la discapacidad. El contenido de cartílago de proteoglicanos se puede reducir sustancialmente, luego de la inducción de diabetes mellitus asociada con inflamación y lesión en la articulación de la rodilla sin embargo, el fármaco antidiabético metformina combinado con el agente antiinflamatorio resveratrol puede prevenir estos efectos nocivos. Por lo tanto, se indujo diabetes insulino dependiente, diabetes mellitus tipo 2 (T2DM) en ratas albinas mediante inyección de estreptozotocina (STZ) (50 mg/kg) después de haber sido alimentadas con dietas ricas en carbohidratos y grasas durante 2 semanas. El grupo protector de ratas que también recibió una inyección única de STZ fue tratado diariamente con metformina (Met; 200 mg/kg) y resveratrol (Res; 30 mg/kg) durante 12 semanas. Tejidos de la articulación de la rodilla fueon retirados y teñidos con histología básica y tinción de proteoglicanos usando microscopía óptica. Las imágenes histológicas en ratas diabéticas mostraban (T2DM) desarrollo de OA visualizadas por una lesión profunda en la articulación de la rodilla y una disminución severa del contenido de proteoglicanos del cartílago articular, los cuales estaban sustancialmente protegidos por Met+Res. Met+Res. También disminuyó significativamente (p< 0,0001) la glucemia inducida por la diabetes, la dislipidemia y los biomarcadores inflamatorios, el factor de necrosis tumoral alfa (TNF-α), la interleucina-6 (IL-6) y la proteína C reactiva de alta sensibilidad (PCR-hs). Además, hubo una correlación significativa entre la OA y la glucemia, la dislipidemia y la inflamación. En conjunto, demostramos una asociación entre el daño de la articulación de la rodilla y los biomarcadores de glucemia, dislipidemia e inflamación en la OA inducida por diabetes, con metformina más resveratrol que brindan efectos protectores.

Suppression of nitrosative stress and inflammation of the knee joint synovium in collagen type ii-induced rheumatoid arthritis by the inhibition of glycogen synthase kinase-3ß / Supresión del estrés nitrosativo e inflamación de la sinovial de la articulación de la rodilla en la artritis reumatoide inducida por colágeno tipo ii mediante la inhibición de la glucógeno sintasa quinasa-3 ß

SUMMARY: Rheumatoid arthritis (RA), an inflammatory autoimmune disease that causes cartilage degradation and tissue destruction, can affect synovial joints such as the knee joint. The link between the nitrosative stress enzyme inducible nitric oxide synthase (iNOS) and the cytokine interleukin-1 (IL-1β) in RA-induced knee joint synovial membrane damage with and without the incorporation of the GSK3β inhibitor TDZD-8 has never been studied. As a result, we used active immunization method with collagen type II (COII) for twenty one days to induce RA in rats. TDZD-8 (1 mg/kg; i.p.) was given daily into matched immunized rats for three weeks after day 21 (COII+TDZD-8). Blood and tissue samples were taken 42 days after immunization. A dramatic increase in rheumatoid factor (RF) blood levels, as well as considerable synovial tissue damage and inflammatory cell infiltration of the synovial membrane, were used to validate the onset of RA following COII immunization. COII immunization increased tissue levels of iNOS protein and IL- 1β mRNA and protein expression, which TDZD-8 suppressed considerably (p<0.0001). Furthermore, there was a significantly (p<0.001) positive correlation between iNOS, inflammatory biomarkers, and RF. We concluded that TDZD-8 reduced RA-induced IL-1β -iNOS axis-mediated arthritis in the rat knee joint synovium.

RESUMEN: La artritis reumatoide (AR), es una enfermedad autoinmune inflamatoria que causa la degradación del cartílago y la destrucción del tejido, pudiendo afectar las articulaciones sinoviales, como la articulación de la rodilla. No se ha estudiado el vínculo entre la óxido nítrico sintasa inducible por la enzima del estrés nitrosativo (iNOS) y la citocina interleucina-1 (IL-1β) en el daño de la membrana sinovial de la articulación de la rodilla provocado por AR con y sin la incorporación del inhibidor de GSK3β TDZD-8. Utilizamos el método de inmunización activa con colágeno tipo II (COII) durante veintiún días para inducir AR en ratas. Se administró TDZD-8 (1 mg/kg; i.p.) diariamente a ratas inmunizadas emparejadas durante tres semanas después del día 21 (COII+TDZD- 8). Se tomaron muestras de sangre y tejido 42 días después de la inmunización. Se observó un gran aumento de los niveles sanguíneos del factor reumatoideo (FR), así como un daño considerable del tejido sinovial e infiltración de células inflamatorias en la membrana sinovial, para validar la aparición de la AR después de la inmunización con COII. La inmunización con COII aumentó los niveles tisulares de la proteína iNOS y la expresión de proteína y ARNm de IL-1β, que TDZD-8 suprimió considerablemente (p<0,0001). Además, hubo una correlación positiva significativa (p<0,001) entre iNOS, biomarcadores inflamatorios y FR. Concluimos que TDZD- 8 redujo la artritis mediada por el eje IL-1β-iNOS inducida por la AR en la sinovial de la articulación de la rodilla de rata.

Lipopolysaccharide induces acute lung injury and alveolar haemorrhage in association with the cytokine storm, coagulopathy and AT1R/JAK/STAT augmentation in a rat model that mimics moderate and severe Covid-19 pathology.

Progress in the study of Covid-19 disease in rodents has been hampered by the lack of angiotensin-converting enzyme 2 (ACE2; virus entry route to the target cell) affinities for the virus spike proteins across species. Therefore, we sought to determine whether a modified protocol of lipopolysaccharide (LPS)-induced acute respiratory distress syndrome in rats can mimic both cell signalling pathways as well as severe disease phenotypes of Covid-19 disease. Rats were injected via intratracheal (IT) instillation with either 15 mg/kg of LPS (model group) or saline (control group) before being killed after 3 days. A severe acute respiratory syndrome (SARS)-like effect was observed in the model group as demonstrated by the development of a "cytokine storm" (>2.7 fold increase in blood levels of IL-6, IL-17A, GM-CSF, and TNF-α), high blood ferritin, demonstrable coagulopathy, including elevated D-dimer (approximately 10-fold increase), PAI-1, PT, and APTT (p < 0.0001). In addition, LPS increased the expression of lung angiotensin II type I receptor (AT1R)-JAK-STAT axis (>4 fold increase). Chest imaging revealed bilateral small patchy opacities of the lungs. Severe lung injury was noted by the presence of both, alveolar collapse and haemorrhage, desquamation of epithelial cells in the airway lumen, infiltration of inflammatory cells (CD45+ leukocytes), widespread thickening of the interalveolar septa, and ultrastructural alterations similar to Covid-19. Thus, these findings demonstrate that IT injection of 15 mg/kg LPS into rats, induced an AT1R/JAK/STAT-mediated cytokine storm with resultant pneumonia and coagulopathy that was commensurate with moderate and severe Covid-19 disease noted in humans.

Suppression of knee joint osteoarthritis induced secondary to type 2 diabetes mellitus in rats by resveratrol: role of glycated haemoglobin and hyperlipidaemia and biomarkers of inflammation and oxidative stress.

Background: We investigated whether the anti-inflammatory and antioxidant agent, resveratrol can inhibit type 2 diabetes mellitus (T2DM)-induced osteoarthritis (OA) in rats and whether it is associated with the suppression of glycaemia, dyslipidemia and inflammatory and oxidative stress biomarkers.Materials and methods: T2DM was induced by streptozotocin (50 mg/kg body weight) and high carbohydrate and fat diet (HCFD). The protective group was put on resveratrol (30 mg/kg) 14 days prior to the induction of diabetes and continued on resveratrol and HCFD until being sacrificed at week 12.Results: Diabetic rats showed a substantial damage to the knee joints and loss of proteoglycans from the articular cartilage, which were effectively but not completly protected by resveratrol. Resveratrol also significantly (p ≤ .0029) reduced diabetic up-regulation of HbA1c, hyperlipidaemia, inflammation and oxidative stress.Conclusions: Resveratrol protects against T2DM-induced OA associated with the inhibition of glycated haemoglobin, dyslipidemia, and biomarkers of oxidative stress and inflammation.

Suppression of glomerular damage and apoptosis and biomarkers of acute kidney injury induced by acetaminophen toxicity using a combination of resveratrol and quercetin.

Acute renal failure induced by a toxic dose of acetaminophen (also known as paracetamol, or APAP) is common in both humans and experimental animal models. Glomerular ultrastructural alterations induced by APAP overdose associated with the suppression of biomarkers of kidney injury have not been investigated before. Also, we investigated whether the combined polyphenolic antioxidants and anti-inflammatory compounds, resveratrol (RES) and quercetin (QUR) can protect against APAP-induced nephrotoxicity. Rats either received a single dose of APAP (2 g/kg) before being sacrificed after 24 hours or were pretreated for 7 days with combined doses of RES (30 mg/kg) and QUR (50 mg/kg) before being given a single dose of APAP and then sacrificed 24 hours post APAP ingestion. APAP significantly (p < 0.05) increased blood levels of urea, creatinine, malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), which were effectively reduced by RES + QUR. In addition, APAP overdose induced the tissue expression of the apoptotic biomarker, p53, and caused profound kidney damage as demonstrated by substantial alterations to the glomerular basement membrane, podocytes, endothelial cells, widening of Bowman's space, and vacuolation of the cells lining the parietal layer, which were substantially protected by RES + QUR. Furthermore, a significant (p < 0.0001) positive correlation was observed between either glomerular basement membrane or podocyte foot processes and these parameters, urea, creatinine, MDA, and TNF-α. Thus, we conclude that APAP induces alterations to the glomerulus ultrastructure, which is protected by resveratrol plus quercetin, which also reduces blood levels of urea and creatinine, and biomarkers of oxidative stress and inflammation.

Paracetamol poisoning induces acute liver injury in rats: inhibition of miR-155/cd45 axis-mediated antioxidant depletion and hepatotoxicity using quercetin and resveratrol / La intoxicación por paracetamol induce daño hepático agudo en ratas: inhibición de la depleción de antioxidantes mediado por el eje miR-155/cd45 y hepatotoxicidad usando quercetina y resveratrol

SUMMARY: Ingestion of an overdose of paracetamol (also called acetaminophen, or APAP) induces hepatotoxicity that can lead to liver failure. The link between the pro-inflammatory microRNA-155 (miR-155) and leukocyte infiltration (CD45) in APAP- antioxidant depletion and liver toxicity with and without the natural polyphenolic compounds, quercetin (QUR) plus resveratrol (RES) has not been previously studied. Therefore, acute hepatic injury was induced in rats by 2 g/kg APAP (single dose, orally) and another group started QUR (50 mg/kg) plus RES (30 mg/kg) treatment one week prior to APAP ingestion. Animals were culled 24 hours post the paracetamol treatment. APAP overdose induced hepatic and blood levels of miR-155 expression, CD45 (leukocyte common antigen) immunostaining, degenerated hepatocytes, and hepatic injury enzymes; alanine aminotransferase (ALT) and aspartate aminotransferase (AST), which were markedly decreased by QUR+RES. Whereas, APAP intoxication ameliorated liver tissue levels of the antioxidants, glutathione peroxidase and superoxide dismutase that were augmented by QUR+RES. Moreover, a significant (p<0.05) correlation between miR-155/CD45 axis and liver tissue injury was observed. These findings show that paracetamol intoxication augments miR- 155/CD45 axis-mediated modulation of antioxidants and liver injury in rats, and is protected by QUR+RES.

RESUMEN: La ingestión de una sobredosis de paracetamol (también llamado acetaminofeno o APAP) induce hepatotoxicidad que puede provocar insuficiencia hepática. El vínculo entre el microARN-155 proinflamatorio (miR-155) y la infiltración de leucocitos (CD45) en el agotamiento de APAP- antioxidante y la toxicidad hepática con y sin los compuestos polifenólicos naturales, quercetina (QUR) más resveratrol (RES) no ha sido previamente investigado. En este estudio, se indujo daño hepático agudo en ratas con 2 g/kg de APAP (dosis única, por vía oral) y otro grupo comenzó el tratamiento con QUR (50 mg/ kg) más RES (30 mg/kg) una semana antes de la ingestión de APAP. Los animales se sacrificaron 24 horas después del tratamiento con paracetamol. La sobredosis de APAP indujo niveles hepáticos y sanguíneos de expresión de miR-155, inmunotinción de CD45 (antígeno leucocitario común), degeneración de los hepatocitos y daño hepático enzimático; alanina aminotransferasa (ALT) y aspartato aminotransferasa (AST), disminuyeron notablemente con QUR+RES. Mientras que la intoxicación con APAP mejoró los niveles de antioxidantes, glutatión peroxidasa y superóxido dismutasa en el tejido hepático los que aumentaron con QUR+RES. Además, se observó una correlación significativa (p<0,05) entre el eje miR-155/CD45 y la lesión del tejido hepático. Estos hallazgos muestran que la intoxicación por paracetamol aumenta la modulación mediada por el eje miR-155/CD45 de los antioxidantes y la lesión hepática en ratas, y está protegida por QUR+RES.

Resveratrol suppresses cholestasis-induced liver injury and fibrosis in rats associated with the inhibition of TGFß1-Smad3-miR21 axis and profibrogenic and hepatic injury biomarkers.

Cholestasis caused by slowing or blockage of bile flow is a serious liver disease that can lead to liver fibrosis and cirrhosis. The link between transforming growth factor beta 1 (TGFß1), Smad family member 3 (Smad3), and microRNA 21 (miR21) in bile duct ligation (BDL)-induced liver fibrosis in the presence and absence of the anti-inflammatory and antioxidant compound, resveratrol (RSV), has not been previously studied. Therefore, we tested whether RSV can protect against BDL-induced liver fibrosis associated with the inhibition of the TGFß1-Smad3-miR21 axis and profibrogenic and hepatic injury biomarkers. The model group of rats had their bile duct ligated (BDL) for 3 weeks before being killed, whereas, the BDL-treated rats were separated into three groups that received 10, 20, and 30 mg/kg RSV daily until the end of the experiment. Using light microscopy and ultrasound examinations, we documented in the BDL group, the development of hepatic injury and fibrosis as demonstrated by hepatocytes necrosis, bile duct hyperplasia, collagen deposition, enlarged liver with increased echogenicity, irregular nodular border and dilated common bile duct, which were more effectively inhibited by the highest used RSV dosage. In addition, RSV significantly (p ≤ 0.0027) inhibited BDL-induced hepatic TGFß1, Smad3, miR21, the profibrogenic biomarker tissue inhibitor of metalloproteinases-1 (TIMP-1), malondialdehyde (MDA), interleukin-17a (IL-17a), and blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin. These findings show that RSV at 30 mg/kg substantially protects against BDL-induced liver injuries, which is associated with the inhibition of TGFß1-Smad3-miR21 axis, and biomarkers of profibrogenesis, oxidative stress, and inflammation.

Silymarin's defensive role against hepatotoxicity induced by amiodarone in albino rats / El efecto defensivo de silimarin contra la hepatotoxicidad inducida por amiodarona en ratas albinas

SUMMARY: Amiodarone (AMD), an orally powerful antidysrhythmic medication that has caused hepatotoxicity on long-term administration, is commonly used across the world. Silymarin ameliorative effects (SLM); this research elucidated the magnitude of the damage to the liver tissue in AMD. We divided 24 albino rats evenly into four groups given daily doses by gastric tube for eight weeks as follows; the 1st group acted as a control group; the 2nd group received SLM; the 3rd group received AMD; and the 4th group received AMD parallel to SLM. Liver tissues prepared for light, electron microscopic and serum samples screened for biomarkers (I)liver injury enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST); (II) oxidative and antioxidant stress, malondialdehyde (MDA) and superoxide dismutase (SOD); and (III) inflammatory markers, tumor necrosis factor-alpha (TNF-a) and interleukin-6 (IL-6). The findings showed that AMD caused hepatic histological changes that included congestion of the blood vessels, leucocytic infiltration and cytoplasmic vacuolation. Ultrastructural degeneration of the mitochondria, endoplasmic reticulum swelling, nuclear pyknosis and increased fat droplets and lysosomes were observed. The biochemical findings showed an increase in the AMD group's ALT and AST activities. The group of rats treated with AMD and SLM, increased the improvements in histology and ultrastructure, while the ALT and AST levels were reduced. Our findings collectively agreed that SLM has a protective impact on AMD hepatotoxicity which can be due to its antioxidant properties.

RESUMEN: La amiodarona (AMD) es un fuerte medicamento antiarrítmico administrado por vía oral que ha causado hepatotoxicidad en la administración a largo plazo utilizado con frecuencia en todo el mundo. Efectos de mejora de la silimarina (SLM); esta investigación analizó la magnitud del daño al tejido hepático en la DMAE. Dividimos 24 ratas albinas de manera uniforme en cuatro grupos que recibieron dosis diarias por sonda gástrica durante ocho semanas de la siguiente manera; el primer grupo fue designado como grupo control; el segundo grupo recibió SLM; el tercer grupo recibió AMD; y el cuarto grupo recibió AMD en paralelo a SLM. Se prepararon tejidos hepáticos para muestras de suero, microscopía de luz y electrónica y se analizaron para biomarcadores (I) enzimas de daño hepático, alanina aminotransferasa (ALT) y aspartato aminotransferasa (AST); (II) estrés oxidativo y antioxidante, malondialdehído (MDA) y superóxido dismutasa (SOD); y (III) marcadores inflamatorios, factor de necrosis tumoral alfa (TNF-a) e interleucina-6 (IL-6). Los hallazgos mostraron que la DMAE genera cambios histológicos hepáticos que incluyen congestión de los vasos sanguíneos, infiltración leucocítica y vacuolación citoplásmica. Se observó una degeneración ultraestructural de las mitocondrias, aumento del retículo endoplásmico, picnosis nuclear y aumento de gotitas de grasa y lisosomas. Los hallazgos bioquímicos mostraron un aumento en las actividades de ALT y AST del grupo AMD. El grupo de ratas tratadas con AMD y SLM, aumentó las mejoras en histología y ultraestructura, mientras que se redujeron los niveles de ALT y AST. Nuestros hallazgos coincidieron colectivamente en que SLM tiene un impacto protector sobre la hepatotoxicidad de AMD debido a sus propiedades antioxidantes.

Suppression of thioacetamide-induced hepatic injury in rats treatment with resveratrol: role of mammalian target of rapamycin (mTOR) cell signaling / Supresión de la lesión hepática inducida por tioacetamida en ratas tratadas con resveratrol: rol de la vía de señalización mTOR (mammalian target of rapamycin)

Chronic hepatotoxicity is a debilitating and frequently life-threatening disease resulting in progressive liver failure. The toxic chemical, thioacetamide (TAA) is used to evaluate hepatoprotective agents, and the polyphenolic compound, resveratrol was proposed as a novel treatment for diseases with hyperactivation of the mammalian target of rapamycin (mTOR) cell signaling pathway. This analysis sought to investigate the potential protective effect of resveratrol against liver injury induced by TAA via the inhibition of hepatic mTOR. Model group rats received several injections of TAA (200 mg/kg; twice a week for 8 weeks) before being sacrificed at week 10 and the protective group was pretreated with resveratrol (20 mg/kg) daily for two weeks prior to TAA injections and continued receiving both agents until the end of the experiment. Harvested liver tissues were examined using light microscopy and liver homogenates were assayed for biomarkers of inflammation and assessed the levels of mTOR protein in all animal groups. In addition, blood samples were assayed for biomarkers of liver injury enzyme. TAA substantially damaged the hepatic tissue of the model group such as infiltration of inflammatory cells, vacuolated cytoplasm, dark pyknotic nuclei, and dilated congested blood vessel that were effectively protected by resveratrol. Resveratrol also significantly (p<0.05) inhibited TAA-induced mTOR, high sensitivity c-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in harvested liver homogenates and blood samples. Thus, we conclude that resveratrol effectively protects against TAA-induced hepatotoxicity in rats, possibly due to the inhibition of mTOR and inflammation.

La hepatotoxicidad crónica es una enfermedad debilitante y potencialmente mortal que produce insuficiencia hepática progresiva. La toxicidad del químico de la tioacetamida (TAA) se utiliza para evaluar los agentes hepatoprotectores y el compuesto polifenólico, resveratrol, se propuso como un nuevo tratamiento para enfermedades con hiperactivación de la vía de señalización celular mTOR (mammalian Target of Rapamycin). Aquí buscamos investigar el posible efecto protector del resveratrol contra la lesión hepática inducida por TAA a través de la inhibición de la vía de señalización mTOR en hepatocitos. Las ratas del grupo modelo recibieron varias inyecciones de TAA (200 mg / kg; dos veces por semana durante 8 semanas) antes de ser sacrificadas en la semana 10 y el grupo protector se trató previamente con resveratrol (20 mg / kg) diariamente durante dos semanas antes de las inyecciones de TAA y continuó recibiendo ambos agentes hasta el final del experimento. Se examinaron los tejidos hepáticos recolectados usando microscopía óptica y se analizaron los homogeneizados hepáticos para detectar biomarcadores de inflamación y se evaluaron los niveles de proteína mTOR en todos los grupos de animales. Además, se analizaron muestras de sangre para detectar biomarcadores de la enzima de lesión hepática. TAA dañó sustancialmente el tejido hepático del grupo modelo, con infiltración de células inflamatorias, citoplasma vacuolado, núcleos picnóticos oscuros y vasos sanguíneos congestionados dilatados que estaban efectivamente protegidos por el resveratrol. El resveratrol también inhibió significativamente (p <0.05) mTOR, proteína C-reactiva (hs-CRP), factor de necrosis tumoral alfa (TNF-α), interleucina-6 (IL-6), alanina aminotransferasa (ALT ) y aspartato aminotransferasa (AST) en las muestras de sangre y de hígados recolectados. En conclusión, el resveratrol protege eficazmente contra la hepatotoxicidad inducida por TAA en ratas, posiblemente debido a la inhibición de mTOR y de la inflamación.

Metformin pretreatment suppresses alterations to the articular cartilage ultrastructure and knee joint tissue damage secondary to type 2 diabetes mellitus in rats.

Osteoarthritis (OA) secondary to diabetes affects millions of people worldwide and can lead to disability. The protective effect of metformin pretreatment against alterations to the articular cartilage ultrastructure induced by type 2 diabetes mellitus (T2DM) associated with the inhibition of oxidative stress and inflammation has not been investigated before. Therefore, we induced T2DM in rats (the model group) using high carbohydrate and fat diet and a single injection of streptozotocin (50 mg/kg body weight). The protective group of rats started metformin (200 mg/kg body weight) treatment 14 days before diabetic induction and continued on metformin until the end of the experiment at week 12. Harvested tissues obtained from knee joints were prepared for staining with hematoxylin and eosin (H&E), safranin o staining, and electron microscopy. Histology images showed that OA was developed in the T2DM rats as demonstrated by a substantial damage to the articular cartilage and profound chondrocyte and territorial matrix ultrastructural alterations, which were partially protected by metformin. In addition, metformin significantly (p < .05) reduced hyperglycemia, glycated hemoglobin (HbA1 c), malondialdehyde (MDA), high sensitivity C-reactive protein (hs-CRP), and interleukin-6 blood levels induced by diabetes. Furthermore, a significant (p ≤ 0.015) correlation between either OA cartilage grade score or the thickness of the articular cartilage and the blood levels of HbA1 c, hs-CRP, MDA, superoxide dismutase (SOD) were observed. These findings demonstrate effective protection of the articular cartilage by metformin against damage induced secondary to T2DM in rats, possibly due to the inhibition of hyperglycemia and biomarkers of oxidative stress and inflammation.