Irisin improves adiposity and exercise tolerance in a rat model of postmenopausal obesity through enhancing adipo-myocyte thermogenesis

The prevalence of obesity and its associated metabolic disorders, along with their healthcare costs, is rising exponentially. Irisin, an adipomyokine, may serve as a critical cross-organ messenger, linking skeletal muscle with adipose tissue and the liver to integrate the energy homeostasis under diet-induced obesity. We aimed to explore the putative role of irisin in the protection against obesity in a postmenopausal rat model by modulating energy expenditure (EE). Bilateral ovariectomy (OVX) was performed. After 3 weeks of recovery, the OVX rats were classified according to their dietary protocol into rats maintained on normal diets (ND) (OVX) or high-fat diet (HFD) groups. The HFD-fed animals were equally divided into OVX/HFD, or irisin-treated OVX/HFD groups. Sham rats, maintained on ND, were selected as the control group. We evaluated anthropometric, EE, and molecular biomarkers of browning and thermogenesis in inguinal white adipose tissue and skeletal muscle, and the activity of the proteins related to mitochondrial long chain fatty acid transport, oxidation, and glycolysis. HFD of OVX further deteriorated the disturbed glucose homeostasis, lipid profile, and the reduced irisin, thermogenic parameters in adipose tissue and skeletal muscle, and EE. Irisin treatment improved the lipid profile and insulin resistance. That was associated with reduced hepatic gluconeogenic enzyme activities and restored hepatic glycogen content. Irisin reduced ectopic lipid infiltration. Irisin augmented EE by activating non-shivering thermogenesis in muscle and adipose tissues and decreasing metabolic efficiency. Our experimental evidence suggests irisin's use as a potential thermogenic agent, therapeutically targeting obesity in postmenopausal patients. Irisin modulates the non-shivering thermogenesis in skeletal muscle and adipose tissue in postmenopausal model.

Melatonin epigenetic potential on testicular functions and fertility profile in varicocele rat model is mediated by Silent information regulator1

BACKGROUND AND PURPOSE

Varicocele is a leading cause of male infertility. Melatonin is a highly pleiotropic neurohormone. We aimed to characterize the melatonin epigenetic potential in varicocele and the involved molecular mechanisms.

EXPERIMENTAL APPROACH

Fifty-two male albino rats were randomly divided into four groups (13 rats each): control (I), melatonin (II), varicocele (III) and melatonin treated varicocele (IV) groups. Left varicocele was induced by partial left renal vein ligation. Reproductive hormones, epididymal sperm functional parameters, testicular 3/17 β-hydroxysteroid dehydrogenases, antioxidant enzymes, malondialdehyde, nicotinamide adenine dinucleotide phosphate oxidase, 8-hydroxy-2'-deoxyguanosine and histopathological/Johnsen's score were evaluated. Flow cytometry and Comet were carried out to explore extent of sperm and testicular DNA damage. Testicular expression of silent information regulator 1 (SIRT1), forkhead transcription factors-class O (type1) (FOXO1), tumour suppressor gene, P53, cation channels of sperm (CatSper) and steroidogenic acute regulatory protein was evaluated by western blot technique. Testicular expression of Bcl-2 and its associated X protein and nuclear factor kappa-light-chain-enhancer of activated B cells were assayed by immunohistochemical staining. Testicular miR-34a expression was quantified by quantitative reverse transcription-polymerase chain reaction.

KEY RESULTS

The varicocele induced testicular histological injury, enhanced oxidative stress, P53-mediated apoptosis, DNA damage and increased testicular miR-34a expression paralleled with down-regulated SIRT1/FOXO axis. Melatonin treatment of varicocele rats displayed antioxidant/anti-apoptotic efficacy and improved reproductive hormones axis, CatSper expression and fertility parameters. MiR-34a/SIRT1/FOXO1 epigenetic axis integrates testicular melatonin mediated intracellular transduction cascades in varicocele.

CONCLUSION AND IMPLICATIONS

Melatonin can be used as an adjuvant therapy to improve varicocele and its complication.

Adverse effect of rheumatoid arthritis on male Wistar rat's fertility: protective role of Costus extract

Rheumatoid arthritis (RA) is a systemic autoimmune complaint. Advanced treatments resort to the traditional herbal therapy. The aim of this study is to assess the protective effect of Costus extract on the fertility of male rats with Freund's adjuvant-induced rheumatoid arthritis. Thirty male adult Wistar rats (190-200 g) were divided into six groups. They were subdivided into three groups; group I was the control group that received distilled water, and groups II and III received two various doses of Costus extract (200 and 400 mg/kg, respectively) for 60 days. Another three groups were subjected to RA induction via Freund's adjuvant. Rats were injected a dose of 0.1 ml of Freund's complete adjuvant (FCA) in the planter area of the left hind paw and then subdivided into 3 groups. Group I of RA-induced rats were given distilled water. The other two groups were given orally (200 and 400 mg/kg dosage of extract, respectively) from the 2nd day of RA induction for 60 days. Sex organ relative weight, sperm concentration assay, testicular histopathology and immunohistochemistry of androgen receptors, TNF α, and BAX protein were determined. The results showed that RA caused a significant decrease in the relative weight of sex organs and sperm count, which were relatively improved by doses of Costus (200, 400 mg/kg). RA induction caused testicular degeneration which markedly enhanced with Costus treatment as shown in histopathological sections. RA caused a reduction in %IHC of androgen receptors and increased expression level of both TNF α and BAX protein. Using IHC, it was revealed that RA caused a reduction in the expression level of androgen receptors and an increase in the expression of both TNF α and BAX protein. We can conclude that Costus speciosus had a potentially valuable role in improving fertility disorders caused by RA.

Long-term exposure to p-Nitrophenol induces hepatotoxicity via accelerating apoptosis and glycogen accumulation in male Japanese quails

p-Nitrophenol (PNP) is the main end product of organophosphorus insecticides and a derivative of diesel exhaust particles. In addition to its unfavorable impact on reproductive functions in both genders, it also has various harmful physiological effects including lung cancer and allergic rhinitis. The identification of the cellular readout that functions in metabolic pathway perpetuation is still far from clear. This research aimed to study the impact of chronic PNP exposure on the health condition of the liver in Japanese quails. Quails were exposed to different concentrations of PNP as follows: 0.0 (control), 0.01mg (PNP/0.01), 0.1mg (PNP/0.1), and 1mg (PNP/1) per kg of body weight for 2.5 months through oral administration. Liver and plasma samples were collected at 1.5, 2, and 2.5 months post-treatment for biochemical, histopathology, and immunohistochemistry assessment. The plasma aspartate aminotransferase (AST) level was assessed enzymatically. The livers were collected for histopathology, glycogen accumulation, proliferating cell nuclear antigen (PCNA), and apoptosis assessment. Our results revealed an irregularity in body weight due to the long-term exposure of PNP with a significant reduction in liver weight. PNP treatment caused histopathological alterations in the hepatic tissues which increased in severity by the long-term exposure. The low dose led to mild degeneration with lymphocytic infiltration, while the moderate dose has a congestion effect with some necrosis; meanwhile severe hepatocyte degeneration and RBCs hemolysis were noticed due to high dose of PNP. Glycogen accumulation increased in hepatocytes by prolonged exposure to p-Nitrophenol with the highest intensity in the group treated by the high dose. Moderate and high doses of PNP resulted in a significant increase in apoptosis and hepatocytes' proliferation at the different time points after treatment. This increase is markedly notable and maximized at 2.5 months post-treatment. The damage occurred in a time-dependent manner. These changes reflected on the plasma hepatic enzyme AST that was clearly increased at 2.5 months of exposure. Therefore, it could be concluded that PNP has profound toxic effects on the liver in cellular level. Taking into consideration the time and dose factors, both have a synergistic effect on the accumulation of glycogen, apoptosis, and cellular proliferation, highlighting the power of cellular investigation which will potentially open the door for earlier medical intervention to counteract this toxicity. Collectively, PNP could have critical hurtful effects on the health of human beings, wild animals as well as livestock.

Assessment of changes in the liver of pregnant female rats and their fetuses following monosodium glutamate administration

Monosodium glutamate (MSG) is a common flavor enhancer and stabilizer for ready-made or packaged foods. This research investigated the impact of MSG on the maternal and fetal liver. The present study was carried out on sixteen mature female Albino rats and eight male rats of reproductive age. The control group was dissected on day 20 of gestation. MSG group was administrated MSG daily at a dosage of 1 g/5 mL/kg body weight from day 0 to day 20 of gestation. The liver function and lipid profile of the control and treated mothers were investigated in the blood sera. The levels of nitric oxide (NO), tumor necrosis factor (TNF-α), superoxide dismutase (SOD), and reduced glutathione (GSH) activities in the liver homogenate of maternal and fetal tissue were assayed, in addition to histopathological, histochemical and immunohistochemical studies were done to the liver tissue. The activities of liver functions and lipid profile significantly altered in the treated mothers with MSG. MSG significantly reduced the SOD and reduced GSH activities in addition to the elevated TNF-α and NO in liver tissue of pregnant mothers and their fetuses. Severe histopathological alterations were observed in both maternal and fetal liver tissues of MSG-treated groups. Moreover, histochemical observations showed a reduction of total polysaccharides in the liver of pregnant rats and fetuses. A significant increase in the percentage area of positive immunoreaction for caspase 3 was observed in the liver of treated rats with MSG compared to the liver of the control. The liver of fetuses treated with MSG revealed an alteration like their mother. This study showed that during the gestational period MSG exposure resulted in several biochemical, histological, and histochemical changes in the maternal and fetal liver tissues which emphasize the toxic effect of MSG.

The effect of dietary supplementation with Nigella sativa (black seeds) mediates immunological function in male Wistar rats

This experiment aimed to investigate the effect of dietary Nigella sativa on the cell-mediated immune response. Eighteen male Wistar rats were divided equally into a control group and treated groups that received black seeds at rates of 30 and 50 g/kg in the diet (Sa30 and Sa50 groups, respectively, for 30 days. The weight gain, feed intake, feed conversion ratio (FCR), and cell-mediated immune response were monitored after the injection of 0.1 mL of 10% phytohemagglutinin (PHA). The intumesce index, serum total antioxidant capacity (TAC), catalase (CAT), interleukin-12 (IL-12), gamma interferon (γ-IF) and tumor necrosis factor alpha (TNF-α) were determined. Histopathological examination and an immunohistochemistry analysis of splenic caspase-3 and CD8 were performed. Nigella sativa significantly improved the weight gain and FCR. Intumesce index of Sa50 group was significantly increased. Nigella sativa significantly increased TAC, CAT, IL-12, γ-IF and TNF-α. A histological examination of PHA-stimulated foot pads showed increased leukocyte infiltration and edema in a dose-dependent pattern. Splenic caspase-3 and CD8 showed significant decreases and increases, respectively, in the Sa30 and Sa50 groups. The results indicate that Nigella sativa seeds exhibit immunostimulatory function through their antioxidant potential, induction of cytokine production, promotion of CD8 expression and reduction of splenic apoptosis.

Evaluation of anti-inflammatory potential of the ethanolic extract of the Saussurea lappa root (costus) on adjuvant-induced monoarthritis in rats

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune disorder characterized by polyarticular symmetrical arthritis. The prevalence of RA is consistent worldwide, affecting about 0.5%-1.0% of the population. The aim of this study was to investigate whether Saussurea lappa (costus) could ameliorate adjuvant arthritis (AA) in the rat for 21 days.

METHODS

Animals were divided into eight groups (n=5/group). Group 1 acted as control, group 2 presented the AA rats (positive control), and groups 3, 4, and 5 were treated with different doses of S. lappa (200, 400, and 600 mg/kg, respectively), whereas groups 6, 7, and 8 were AA rats and orally administered with S. lappa (200, 400, and 600 mg/kg, respectively). The changes caused by chronic inflammation were evaluated through the measurement of ankle circumference (AC). Serum C-reactive protein (CRP), interleukins (IL-1β and IL-6), tumor necrosis factor α (TNF-α), total oxidative capacity (TOC), and total antioxidant capacity (TAC) were determined.

RESULTS

Saussurea lappa dose-dependently alleviated the severity of the disease based on the reduction in AC and on the clinical scores of the histological study. Histopathological examination proved that S. lappa decreased the infiltration of inflammatory cells and synovial hyperplasia as well as protected joint destruction. Saussurea lappa reduced the serum levels of CRP, TNF-α, IL-1β, and IL-6, reduced the TOC, and improved the TAC as compared with AA rats.

CONCLUSIONS

The S. lappa extract has potentially useful anti-arthritic activity as well as improves the immune and antioxidant responses of adjuvant-induced monoarthritis in rats.