Computational and Experimental Approaches Exploring the Role of Hesperetin in Improving Autophagy in Rat Diabetic Retinopathy.

Diabetic retinopathy (DR) is a debilitating diabetic disorder of the retinal microvasculature and the main cause of avoidable blindness in old people. Hesperetin is a plant flavanone largely abundant in citrus species with neuroprotective properties in animal models. This study aimed to explore the neuroprotective and autophagy-enhancing effect of hesperetin in rats with DR. Twenty-four male rats were utilized and allocated to groups: (i) the vehicle group, (ii) DR group and (iii-iv) the DR + hesperetin (50 and 100 mg/kg) groups. Treatment with hesperetin continued for 6 weeks. After the rats were euthanized, their eyes were dissected to detect the biochemical and histological changes in the retinas. Quantification of autophagy markers, beclin 1/LC3/p62, and inflammation markers was performed. Histopathologic changes were investigated after staining with hematoxylin and eosin and periodic acid-Schiff (PAS). Results demonstrated that hesperetin decreased the PAS staining in diabetic rats and attenuated histopathological changes and restored retinal organization and thickness of layers in hematoxylin and eosin staining. Moreover, hesperetin reduced the level of mRNA expression for TNF-α (4.9-fold), IL-1ß (4.15-fold), IL-6 (4.6-fold) and NFκB (5.2-fold), as well as the protein level. This was accompanied by induction of autophagy proteins, beclin 1 and LC3-II. Our results afford evidence that hesperetin is effective in alleviating the pathology of DR via suppressing the inflammatory burden and induction of autophagy. After extensive clinical examinations, hesperetin may prove to be a useful option for treatment of DR.

Leflunomide-induced cardiac injury in adult male mice and bioinformatic approach identifying Nrf2/NF-κb signaling interplay.

Leflunomide (LFND) is an immunosuppressive and immunomodulatory disease-modifying antirheumatic drug (DMARD) that was approved for treating rheumatoid arthritis. LFND-induced cardiotoxicity was not fully investigated since its approval. We investigated the cardiac injury in male mice and identified the role of nuclear factor erythroid 2-related factor 2/nuclear factor-κ B (Nrf2/NF-κB) signaling. Male albino mice were assigned into five groups as control, vehicle, and LFND (2.5, 5, and 10 mg/kg). We investigated cardiac enzymes, histopathology, and the mRNA expression of Nrf2, NF-κB, BAX, and tumor necrosis factor-α (TNF-α). The bioinformatic study identified the interaction between LFND and Nrf2/NF-κB signaling; this was confirmed by amelioration in mRNA expression (0.5- to 0.34-fold decrease in Nrf2 and 2.6- to 4.61-fold increases in NF-κB genes) and increased (1.76- and 2.625-fold) serum creatine kinase (CK) and 1.38- and 2.33-fold increases in creatine kinase-MB (CK-MB). Histopathological results confirmed the dose-dependent effects of LFND on cardiac muscle structure in the form of cytoplasmic, nuclear, and vascular changes in addition to increased collagen deposits and apoptosis which were increased compared to controls especially with LFND 10 mg/kg. The current study elicits the dose-dependent cardiac injury induced by LFND administration and highlights, for the first time, dysregulation in Nrf2/NF-κB signaling.

Protective Effect of Topiramate against Diabetic Retinopathy and Computational Approach Recognizing the Role of NLRP3/IL-1ß/TNF-α Signaling.

The possible impact of topiramate against diabetic retinopathy (DREN) and its molecular mechanisms in relation to the nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome has not been studied before. Thus, in the present study, we aimed to utilize a computational approach to investigate the possible protective effect of topiramate on experimental DREN and explore its impact on NLRP3/interlukin-1ß signaling and brain-derived neurotrophic factor (BDNF) expression. Male albino mice were distributed to four experimental groups and assigned the following categorizations: (i) saline, (ii) diabetic, (iii) diabetic + topiramate 10 mg/kg and (iv) diabetic + topiramate 30 mg/kg. We observed shrinkage of total retinal thickness and elevation in retinal glutamate, malondialdehyde, NLRP3 and interlukin-1ß but decreased glutathione (GSH) levels in the diabetic mice. Additionally, retinal ultra-structures in the diabetic group showed abnormalities and vacuolations in the pigmented epithelium, the photoreceptor segment, the outer nuclear layer, the inner nuclear layer and the ganglion cell layer (GCL). Mice treated with topiramate 10 or 30 mg/kg showed downregulation in retinal malondialdehyde, NLRP3 and interlukin-1ß levels; improvements in the retinal pathologies; enhanced immunostaining for BDNF and improved ultra-structures in different retinal layers. Overall, the current results suggest topiramate as a neuroprotective agent for DREN, and future studies are warranted to further elucidate the mechanism of its protective action.

Formulation and Characterization of O/W Nanoemulsions of Hemp Seed Oil for Protection from Steatohepatitis: Analysis of Hepatic Free Fatty Acids and Oxidation Markers.

Non-alcoholic steatohepatitis (NASH) is a common type of metabolic liver disease which is characterized by fatty changes associated with hepatocyte injury, lobular inflammation, and/or liver fibrosis. Nanoemulsions are kinetically stable colloidal systems characterized by small droplet size. Hemp seed oil is a natural oil derived from Cannabis sativa seeds. The current study was designed to formulate nanoemulsion preparations of hemp seed oil with promising enhanced biological activity against high fat (HF) diet induced NASH in rats. Four nanoemulsion formulas (NEFs) were formulated based on high-pressure homogenization technique and evaluated for droplet size, zeta potential (ZP), polydispersity index (PDI), electrical conductivity, pH, and viscosity, as well as the preparation stability. The best NEF was selected to perform an in vivo rat study; selection was based on the smallest droplet size and highest physical stability. Results showed that NEF#4 showed the best physiochemical characters among the other preparations. Twenty male rats were assigned to four groups as follows: normal, NASH control, NASH + hemp seed oil and NASH + hemp seed oil NEF4. The rats were tested for body weight (BWt) change, insulin resistance (IR) and hepatic pathology. The hemp seed NEF#4 protected against NASH progression in rats and decreased the % of BWt gain compared to the original Hemp seed oil. NEF#4 of Hemp seed oil showed greater protective activity against experimental NASH and IR in rats. Hence, we can consider the nanoemulsion preparations as a useful tool for enhancing the biological action of the hemp seed oil, and further studies are warranted for application of this technique for preparing natural oils aiming at enhancing their activities.

Saponin-rich extract of Tribulus terrestris alleviates systemic inflammation and insulin resistance in dietary obese female rats: Impact on adipokine/hormonal disturbances.

Tribulus terrestris saponins (TTS) have been longley used as an overall tonic and recent studies showed they influence inflammatory conditions. We examined the ameliorative effect of a commercial formula of a saponin-rich extract of TT in a model of dietary obesity in female rats focusing on their ability to control the inflammatory burden, insulin resistance (IR), adipokine expression and the related reproductive system pathologies. Female rats were fed with high fat diet (HFD) for 14 weeks to launch diet-induced obesity; they were assigned as: the obese control female rats (OFR) which received no treatment and TTS (5 and 10 mg/kg/day) treated rats; they were compared to a normal rat group. We determined the IR index, serum/tissue inflammatory cytokines, and adipose tissue adipokine expression and examined the secondary ovarian pathologies. Body weight gain, serum triglycerides and IR (>5-fold) in the OFR group were greater than the normal group; TTS lessened these parameters compared with the OFR group. TTS, at 10 mg/kg dose, ameliorated mRNA expression of leptin and visfatin genes in addition to serum inflammatory cytokine levels. Moreover, TTS corrected the hyperprolactinemia and other hormonal disturbances and ameliorated the ovarian pathologies. This study highlighted that the anti-inflammatory properties of TTS helped in alleviation of IR and body weight gain in OFR. Upon correction of obesity manifestations, the gonadal hormone dysregulations and ovarian pathologies were subsequently ameliorated. We can consider TTS as a promising candidate that may alleviate the inflammatory burden, IR and adipokine expression in obesity and hence prevent the secondary gonadal complications in female subjects if appropriate clinical studies are available.

Pretreatment with Coenzyme Q10 Combined with Aescin Protects against Sepsis-Induced Acute Lung Injury.

Sepsis-associated acute lung injury (ALI) is a critical condition characterized by severe inflammatory response and mitochondrial dysfunction. Coenzyme Q10 (CoQ10) and aescin (AES) are well-known for their anti-inflammatory activities. However, their effects on lipopolysaccharide (LPS)-induced lung injury have not been explored yet. Here, we asked whether combined pretreatment with CoQ10 and AES synergistically prevents LPS-induced lung injury. Fifty male rats were randomized into 5 groups: (1) control; (2) LPS-treated, rats received a single i.p. injection of LPS (8 mg/kg); (3) CoQ10-pretreated, (4) AES-pretreated, or (5) combined-pretreated; animals received CoQ10 (100 mg/kg), AES (5 mg/kg), or both orally for 7 days before LPS injection. Combined CoQ10 and AES pretreatment significantly reduced lung injury markers; 52.42% reduction in serum C-reactive protein (CRP), 53.69% in alkaline phosphatase (ALKP) and 60.26% in lactate dehydrogenase (LDH) activities versus 44.58, 37.38, and 48.6% in CoQ10 and 33.81, 34.43, and 39.29% in AES-pretreated groups, respectively. Meanwhile, combination therapy significantly reduced interleukin (IL)-1ß and tumor necrosis factor (TNF)-α expressions compared to monotherapy (p < 0.05). Additionally, combination therapy prevented LPS-induced histological and mitochondrial abnormalities greater than separate drugs. Western blotting indicated that combination therapy significantly suppressed nucleotide-binding oligomerization domain (NOD)-like receptors-3 (NLRP-3) inflammasome compared to separate drugs (p < 0.05). Further, combination therapy significantly decreased the expression of signaling cascades, p38 mitogen-activated protein kinases (p38 MAPK), nuclear factor kappa B (NF-κB)-p65, and extracellular-regulated kinases 1/2 (ERK1/2) versus monotherapy (p < 0.05). Interestingly, combined pretreatment significantly downregulated high mobility group box-1 (HMGB1) by 72.93%, and toll-like receptor 4 (TLR4) by -0.93-fold versus 61.92%, -0.83-fold in CoQ10 and 38.67%, -0.70-fold in AES pretreatment, respectively. Our results showed for the first time that the enhanced anti-inflammatory effect of combined CoQ10 and AES pretreatment prevented LPS-induced ALI via suppression of NLRP-3 inflammasome through regulation of HMGB1/TLR4 signaling pathway and mitochondrial stabilization.