Evaluating Peptides of Picrorhiza kurroa and Their Inhibitory Potential against ACE, DPP-IV, and Oxidative Stress.

Picrorhiza kurroa Royle ex Benth. is a high-altitude plant having great medicinal value. However, its medicinal value at the peptide level is still unknown, which limits its utility in the development of peptide-based therapeutics. Here, we identify 65 peptides fromP. kurroa hydrolysate. Sequence analysis suggests that one novel bioactive peptide, ASGLCPEEAVPRR (BP1), has antioxidant potential and shows angiotensin-converting enzyme (ACE) and dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. The molecular docking study showed that BP1 has a lower binding energy and strong affinity toward active pockets of ACE and DPP-IV, which explains its higher ACE [IC50 = 59.90 ± 9.52 µg/mL (43.40 µM)] and DPP-IV [IC50 = 3.04 ± 0.26 µg/mL (2.2 µM)] inhibitory activities. BP1 protects HEK293 cells from H2O2-induced oxidative damage by inhibiting intracellular reactive oxygen species (ROS) and malondialdehyde accumulation and activating the intrinsic antioxidant defense system. Additionally, phase-contrast microscopy studies revealed that pre-treatment of BP1 to HEK293 cells before exposure to H2O2 retains the normal morphology and blocks apoptosis. Furthermore, it also suppresses ROS-induced mitochondrial apoptosis via restoring the mitochondrial membrane potential (ΔΨm) and inhibiting caspase 3/7 activity. Therefore, BP1 has antioxidant potential and ACE and DPP-IV inhibitory activities that could be used for peptide-based formulation(s) in pharmaceuticals to treat diabetes, cardiovascular diseases, and other diseases associated with ROS.

Apoptosis and cell cycle arrest of leukemic cells by a robust and stable L-asparaginase from Pseudomonas sp. PCH199.

Biomolecules obtained from microorganisms living in extreme environments possess properties that have pharmacokinetic advantages. Enzyme assay revealed recombinant L-ASNase, an extremozyme from Pseudomonas sp. PCH199 is to be highly stable with 90 % activity (200 h) at 37 °C. The stability of the enzyme in human serum (50 % activity maintained in 63 h) reveals high therapeutic potential with less dosage. The enzyme exhibited cytotoxicity to K562 blood cancer cell lines with IC50 of 0.37 U/mL without affecting the IEC-6 normal epithelial cell line. Due to the depletion of L-asparagine, K562 cells experience nutritional stress that results in the abruption of metabolic processes and eventually leads to apoptosis. Comparative studies on MCF-7 cells also revealed the same fate. Due to nutritional stress induced by L-ASNase treatment, mitochondrial membrane potential was lost, and reactive oxygen species were increased to 48 % (K562) and 21 % (MCF-7) as indicated by flow cytometric analysis. DAPI staining with prominent nuclear morphological changes visualized under the fluorescent microscope confirmed apoptosis in both cancer cells. Treatment increases pro-apoptotic Bax protein, and eventually, the cell cycle is arrested at the G2/M phase in both cell lines. Therefore, the current study paves the way for PCH199 L-ASNase to be considered a potential chemotherapeutic agent for treating acute lymphoblastic leukemia.

S-Adenosylmethionine Negatively Regulates the Mitochondrial Respiratory Chain Repressor MCJ in the Liver.

MCJ (Methylation-Controlled J protein), an endogenous repressor of the mitochondrial respiratory chain, is upregulated in multiple liver diseases but little is known about how it is regulated. S-adenosylmethionine (SAMe), the biological methyl donor, is frequently depleted in chronic liver diseases. Here, we show that SAMe negatively regulates MCJ in the liver. While deficiency in methionine adenosyltransferase alpha 1 (MATα1), enzyme that catalyzes SAMe biosynthesis, leads to hepatic MCJ upregulation, MAT1A overexpression and SAMe treatment reduced MCJ expression. We found that MCJ is methylated at lysine residues and that it interacts with MATα1 in liver mitochondria, likely to facilitate its methylation. Lastly, we observed that MCJ is upregulated in alcohol-associated liver disease, a condition characterized by reduced MAT1A expression and SAMe levels along with mitochondrial injury. MCJ silencing protected against alcohol-induced mitochondrial dysfunction and lipid accumulation. Our study demonstrates a new role of MATα1 and SAMe in reducing hepatic MCJ expression.

Phloretin and phlorizin mitigates inflammatory stress and alleviate adipose and hepatic insulin resistance by abrogating PPARγ S273-Cdk5 interaction in type 2 diabetic mice.

AIMS: The rising prevalence of type 2 diabetes mellitus (T2DM) and accompanying insulin resistance is alarming globally. Natural and synthetic agonists of PPARγ are potentially attractive candidates for diabetics and are known to efficiently reverse adipose and hepatic insulin resistance, but related side effects and escalating costs are the causes of concern. Therefore, targeting PPARγ with natural ligands is advantageous and promising approach for the better management of T2DM. The present research aimed to assess the antidiabetic potential of phenolics Phloretin (PTN) and Phlorizin (PZN) in type 2 diabetic mice. MAIN METHODS: In silico docking was performed to check the effect of PTN and PZN on PPARγ S273-Cdk5 interactions. The docking results were further validated in preclinical settings by utilizing a mice model of high fat diet-induced T2DM. KEY FINDINGS: Computational docking and further MD-simulation data revealed that PTN and PZN inhibited the activation of Cdk5, thereby blocking the phosphorylation of PPARγ. Our in vivo results further demonstrated that PTN and PZN administration significantly improved the secretory functions of adipocytes by increasing adiponectin and reducing inflammatory cytokine levels, which ultimately reduced the hyperglycaemic index. Additionally, combined treatment of PTN and PZN decreased in vivo adipocyte expansion and increased Glut4 expression in adipose tissues. Furthermore, PTN and PZN treatment reduced hepatic insulin resistance by modulating lipid metabolism and inflammatory markers. SIGNIFICANCE: In summary, our findings strongly imply that PTN and PZN are candidates as nutraceuticals in the management of comorbidities related to diabetes and its complications.

Catechins prevent obesity-induced kidney damage by modulating PPARγ/CD36 pathway and gut-kidney axis in rats.

Obesity is an epidemic and a growing public health concern worldwide. It is one of the significant risk factors for developing chronic kidney disease. In the present study, we evaluated the preventive effect of green tea catechins (GTC) against obesity-induced kidney damage and revealed the underlying molecular mechanism of action. Various green tea catechins were quantified in the catechins-rich fraction using HPLC. In vitro, the palmitic and oleic acid-treated NRK-52E cells showed reduced fat accumulation and modulated expressions of PPARγ, CD36, and TGFß after GTC treatment. In vivo, rats were fed with a high-fat diet (HFD), and the effect of GTC was assessed at 150 and 300 mg/kg body weight doses. HFD-fed rats showed a significant reduction in weight gain and improved serum creatinine, urea, and urine microalbumin levels after GTC treatment. The improved adipokines and insulin levels in GTC treated groups indicated the insulin-sensitizing effect. Histopathology revealed reduced degenerative changes, fibrous tissue deposition, and mesangial matrix proliferation in GTC treated groups. GTC treatment also downregulated the gene expressions of lipogenic and inflammatory factors and improved the altered expressions of CD36 and PPARγ in the kidney tissue. Further, GTC prevented gut dysbiosis in rats by promoting healthy microbes like Akkermansia muciniphila and Lactobacillus reuteri. Faecal metabolome revealed reduced saturated fatty acids, and improved amino acid levels in the GTC treated groups, which help to maintain gut health and metabolism. Overall, GTC prevented obesity-induced kidney damage by modulating PPARγ/CD36 signaling and maintaining gut health in rats.

Metagenomic signatures reveal the key role of phloretin in amelioration of gut dysbiosis attributed to metabolic dysfunction-associated fatty liver disease by time-dependent modulation of gut microbiome.

The importance of gut-liver axis in the pathophysiology of metabolic dysfunction-associated fatty liver disease (MAFLD) is being investigated more closely in recent times. However, the inevitable changes in gut microbiota during progression of the disease merits closer look. The present work intends to assess the time-dependent gut dysbiosis in MAFLD, its implications in disease progression and role of plant-derived prebiotics in its attenuation. Male C57BL/6J mice were given western diet (WD) for up to 16 weeks and phloretin was administered orally. The fecal samples of mice were collected every fourth week for 16 weeks. The animals were sacrificed at the end of the study and biochemical and histological analyses were performed. Further, 16S rRNA amplicon sequencing analysis was performed to investigate longitudinal modification of gut microbiome at different time points. Findings of our study corroborate that phloretin alleviated the metabolic changes and mitigated circulating inflammatory cytokines levels. Phloretin treatment resists WD induced changes in microbial diversity of mice and decreased endotoxin content. Prolonged exposure of WD changed dynamics of gut microbiota abundance and distribution. Increased abundance of pathogenic taxa like Desulfovibrionaceae, Peptostreptococcus, Clostridium, and Terrisporobacter was noted. Phloretin treatment not only reversed this dysbiosis but also modulated taxonomic signatures of beneficial microbes like Ruminococcus, Lactobacillus, and Alloprevotella. Therefore, the potential of phloretin to restore gut eubiosis could be utilized as an intervention strategy for the prevention of MAFLD and related metabolic disorders.

Amorphous solid dispersion augments the bioavailability of phloretin and its therapeutic efficacy via targeting mTOR/SREBP-1c axis in NAFLD mice.

The escalating incidences of non-alcoholic fatty liver disease (NAFLD) and associated metabolic disorders are global health concerns. Phloretin (Ph) is a natural phenolic compound, that exhibits a wide array of pharmacological actions including its efficacy towards NAFLD. However, poor solubility and bioavailability of phloretin limits its clinical translation. Here, to address this concern we developed an amorphous solid dispersion of phloretin (Ph-SD) using Soluplus® as a polymer matrix. We further performed solid-state characterization through SEM, P-XRD, FT-IR, and TGA/DSC analysis. Phloretin content, encapsulation efficiency, and dissolution profile of the developed formulation were evaluated through reverse phase HPLC. Finally, the oral bioavailability of Ph-SD and its potential application in the treatment of experimental NAFLD mice was investigated. Results demonstrated that the developed formulation (Ph-PD) augments the dissolution profile and oral bioavailability of the native phloretin (Ph). In NAFLD mice, histopathological studies revealed the preventive effect of Ph-SD on degenerative changes, lipid accumulation, and inflammation in the liver. Ph-SD also improved the serum lipid profile, ALT, and AST levels and lowered the interleukin-6 and tumor necrosis factor-α levels in the liver. Further, Ph-SD reduced fibrotic changes in the liver tissues and attenuates NAFLD progression by blocking the mTOR/SREBP-1c pathway. In a nutshell, the results of our study strongly suggest that Ph-SD has the potential to be a therapeutic candidate in the treatment of NAFLD and can be carried forward for further clinical studies.

Phloretin mitigates oxidative injury, inflammation, and fibrogenic responses via restoration of autophagic flux in in vitro and preclinical models of NAFLD.

Nonalcoholic fatty liver disease (NAFLD) with growing incidences is a major health concern worldwide. Alteration in cellular redox homeostasis and autophagy plays a critical role in the progression of NAFLD to more severe outcomes. The lack of safe and effective therapy for the disease necessitates the exploration of new therapeutic compounds. Therefore, in the present study, we investigated the potential of phloretin to maintain redox equilibrium and prevent disease progression via modulation of autophagy in NAFLD. Free fatty acid exposed Huh7 cells were used to evaluate the efficacy of phloretin in vitro. Further, phloretin was administered orally to western diet induced NAFLD in C57BL/6J mice at different doses. The chronic exposure to fatty acids and the western diet triggered lipid accumulation in the Huh7 cells and western diet-fed mice liver, respectively. In addition, mitochondrial dysfunction, oxidative stress, inflammation and decreased hepatic autophagy were observed in disease condition. Phloretin encouraged autophagy mediated hepatic lipid clearance and restored mitochondrial membrane potential and redox homeostasis. It also reduced histological injury by reducing hepatic lipogenesis and facilitating fatty acid oxidation. Moreover, findings of the study also revealed the mitigatory effect of phloretin on inflammatory and fibrogenic markers. Altogether, the study suggested that phloretin effectively attenuates NAFLD progression via upregulating autophagy-mediated lipid breakdown and inhibits oxidative damage, hepatic inflammation and fibrosis.

Beverages and Non-alcoholic fatty liver disease (NAFLD): Think before you drink.

BACKGROUND & AIMS: Beverages and Non-alcoholic fatty liver disease (NAFLD) both the terms are associated with westernized diet and sedentary lifestyle. Throughout recent decades, dietary changes have boosted demand of beverages to meet the liquid consumption needs, among which rising consumption of several calorie-rich beverages have increased the risk of fatty liver disease. Meanwhile, certain beverages have capacity to deliver many unanticipated health benefits thereby reducing the burden of NAFLD and metabolic diseases. The present review therefore addresses the increasing interconnections between beverages intake among population, dietary patterns and the overall effect of these beverage on the development and prevention of NAFLD. Methods In the present review, some frequently consumed beverage groups have been analyzed in light of their role in the advancement and prevention of NAFLD, including sugar sweetened, hot and alcoholic beverages. The nutritional composition of different beverages makes the progression of NAFLD distinctive. RESULTS: The ingestion of sugar-rich beverages has demonstrated the metabolic burden and in all cases, raises the risk of NAFLD, while intake of coffee and tea has decreased this risk without any significant adverse effects. In some cases, low to moderate alcohol intake has been shown to minimize the risk of advanced fibrosis and NAFLD-mortality. CONCLUSION: Together, this review discusses and supports work on new dietary approaches and clinical studies to accomplish nutrition-oriented NAFLD care by improving the drinking habits.

Tinospora cordifolia activates PPARγ pathway and mitigates glomerular and tubular cell injury in diabetic kidney disease.

BACKGROUND: Diabetic Kidney Disease (DKD) is a common complication of diabetes and a leading cause of end-stage renal disease progression. Therefore, therapeutic strategies are desirable to mitigate the progression of disease into more severe consequences. Hypothesis/Purpose:Tinospora cordifolia is a traditionally known antidiabetic plant; however, its effect against DKD remains unexplored. Therefore, in the present study, we assessed the efficacy and mechanism of action of Tinospora cordifolia extract (TC) against DKD. METHODS: The molecular interaction of the various phytoconstituents of TC with PPARγ were analyzed in silico. The effect of TC was studied on the viability, cell cycle, and gene expressions (PPARγ, TGFß, and αSMA) in high glucose treated NRK-52E and SV40 MES13 cells. Further, streptozotocin-induced diabetic rats were treated with TC for eight weeks, and the effects on different biochemical, histological and molecular parameters were studied. RESULTS: In silico analysis revealed the integration of various phytoconstituents of TC with PPARγ. It further increased PPARγ and decreased TGFß and αSMA expressions in NRK-52E and SV40 MES13 cells. In diabetic rats, TC improved the fasting blood glucose, serum urea, and creatinine levels. It also lowered the urine microalbumin and advanced glycation end products (AGEs) levels. Histopathological studies revealed the preventive effect of TC on degenerative changes, mesangial proliferation and glomerular hypertrophy. Further, it reduced the inflammation and fibrotic changes in the kidney tissue estimated by various markers. The kidney tissue and gene expression analysis revealed the augmented levels of PPARγ after TC treatment. CONCLUSION: In conclusion, TC exerted the protective effect against DKD by inhibiting inflammation and fibrogenesis through the activation of PPARγ dependent pathways.

Dendrimer-conjugated podophyllotoxin suppresses DENA-induced HCC progression by modulation of inflammatory and fibrogenic factors.

Podophyllotoxin has been explored as an anticancer, antiviral, and antibacterial agent; however, its low water solubility and toxicity limit its use. In this study, the efficacy of a more soluble and less toxic polyamidoamine (PAMAM) dendrimer-conjugated podophyllotoxin (DPODO) was evaluated against chemically induced hepatocellular carcinoma (HCC) in mice. HCC was induced by giving 0.01% diethylnitrosamine (DENA) in drinking water for 16 weeks. The HCC-induced mice were treated with 10 or 20 mg per kg body weight DPODO. The DENA administration led to HCC development, characterized by anisocytosis, karyomegaly, inflammation and degenerative changes in the liver. The DPODO treatment at 10 mg and 20 mg doses significantly reduced the histopathological changes in liver tissue. The DPODO treatment also significantly lowered the levels of inflammatory markers IL-6 and NF-κB in serum and tissue, respectively. Further, the treatment also significantly reduced fibrous tissue deposition in the liver, which was further confirmed by the reduced mRNA levels and tissue expression of fibrogenic markers TGF-ß and α-SMA in the liver. The results of the present study indicate that DPODO treatment suppresses the progression of HCC by modulating the inflammatory and fibrogenic factors, which play important roles in HCC development.