The aim of this work was to study age-related changes in the behaviour of adult Wistar rats using the open field (OF) and elevated plus maze (EPM) tests. Behavioural changes related to motor activity and anxiety were of particular interest. Results showed that as male and female rats progressed from 2 to 5 months of age there was a decrease in the level of motor and exploratory activities, and an increase in the level of anxiety. Age-related changes were dependent upon initial individual characteristics of behaviour. For example, animals that demonstrated high motor activity at 2 months become significantly less active by 5 months, and animals that showed a low level of anxiety at 2 months become more anxious by 5 months. Low-activity and high-anxiety rats did not show any significant age-related changes in OF and EPM tests from 2 to 5 months of age, except for a decrease in the number of rearings in EPM. Significant individual differences in the behaviour of rats in OF and EPM tests observed at 2 months were not apparent by 5 months.

Leptin, acting centrally or peripherally, has complex effects on cardiac remodeling and heart function. We previously reported that central leptin exerts an anti-hypertrophic effect in the heart via cardiac PPARβ/δ activation. Here, we assessed the impact of central leptin administra-tion and PPARβ/δ inhibition on cardiac function. Various cardiac properties, including QRS du-ration, R wave amplitude, heart rate (HR), ejection fraction (EF), end-diastolic left ventricular mass (EDLVM), end-diastolic volume (EDV), and cardiac output (CO) were analyzed. Central leptin infusion increased cardiac PPARβ/δ protein content and decreased HR, QRS duration and R wave amplitude. These changes induced by central leptin suggested a decrease in the ventricu-lar wall growth which was confirmed by MRI. In fact, the EDLVM was reduced by central leptin, while increased in rats co-treated with leptin and GSK0660, a selective antagonist of PPARβ/δ ac-tivity. In summary, central leptin plays a dual role in cardiac health, potentially leading to ven-tricular atrophy and improving heart function when PPARβ/δ signaling is intact. The protective effects of leptin are lost by PPARβ/δ inhibition, underscoring the importance of this pathway. These findings highlight the therapeutic potential of targeting leptin and PPARβ/δ pathways to combat cardiac alterations and heart failure, particularly, in the context of obesity

Context: Persea Americana is reported to have medicinal value. Calcium Carbide (CaC2), a fruit-ripening agent, has been shown to be toxic to body organs. Objective: To determine the effect of avocado seed extract (ASE) on CaC2-induced hepatotoxicity in rats. Methodology: Four experimental groups, each of 5 adult wistar rats were fed respectively with normal diets (group A); 250mg/kg ASE (group B); 100mg/kg CaC2 (group C); combination of 100mg/kg CaC2 and 250mg/kg ASE – group D. Changes in the rats’ behaviours, body weights, and liver function were assessed over 21 days. Data were analyzed using SPSS. The cumulated rat weights, rat liver weights and serum liver enzyme levels for groups B, C, and D rats were compared to group A. Results: Abnormal behavior was most observed in group C rats. Rats in group A showed a significant increase in weight before and three weeks following administration of feeds while rats in groups B, C, and D showed significant decrease in weight – more marked in group C rats. Only the mean liver weights of rats in group C showed significant decrease compared to that in group A, p = 0.001. Similarly, only the cumulated liver enzyme levels of rats in group C demonstrated significant increase when compared to group A rats - indicating hepatotoxicity. Conclusion In this study, hepatotoxicity occurred in CaC2-administered rats. However, the combination of CaC2 and ASE showed no liver toxicity indicating a mitigating effect of ASE to CaC2-induced hepatotoxicity.

This study investigates the healing action of topical formulations based on Libidibia ferrea fruits in cutaneous wounds induced in Wistar rats. Three types of preparations were evaluated: glycolic extract, infusion, and gel. The phytochemical compounds present in the preparations, such as tannins and flavonoids, are known for their antioxidant, anti-inflammatory, and antimicrobial properties, which are essential for the healing process, histopathological methods evaluated healing, including analysis of epithelialization, granulation tissue formation, and collagen deposition. The results demonstrated that the preparations accelerated the healing process, with a more significant deposition of type I collagen in the groups treated with infusion and glycolic extract, suggesting a more advanced tissue repair process. The infusion demonstrated the best healing results, possibly due to the higher flavonoid content. The findings reinforce the therapeutic potential of Libidibia ferrea in the development of natural healing agents.

Populations with essential hypertension have a high risk of nonalcoholic steatohepatitis (NASH). In this study, we investigated the mechanism that underlies the progression of hypertension-associated NASH by comparing differences in the development of high fat and cholesterol (HFC) diet-induced NASH among three strains of rats, i.e., two hypertensive strains comprising spontaneously hypertensive rats and the stroke-prone spontaneously hypertensive 5/Dmcr, and the original Wistar Kyoto rats as the normotensive control. We investigated histopathological changes and molecular signals related to inflammation in the liver after feeding with the HFC diet for 8 weeks. The diet induced severe lobular inflammation and fibrosis in the livers of the hypertensive rats, whereas it only caused mild steatohepatitis in the normotensive rats. Increased activation of proinflammatory signaling (transforming growth factor-β1/mitogen-activated protein kinases pathway) was observed in the hypertensive strains fed with the HFC diet. In addition, the HFC diet suppressed the nuclear factor erythroid 2-related factor 2 pathway in the hypertensive rats and led to lower increases in the hepatic expression of heme oxygenase-1, which has anti-oxidative and anti-inflammatory activities. In conclusion, these signaling pathways might play crucial roles in the development of hypertension-associated NASH.

This study aimed to investigates obesity-related glomerulopathy (ORG) at cellular, structural, and transcriptomic levels. Thirty Wistar rats were randomized into two groups: control (n=15) and study groups (n=15) that were fed a standard (SD) and high-fat diet (HFD), respectively. After 10 weeks, the weight, kidney function, histological features, and transcriptomic changes were assessed. HFD group exhibited increased weight gain (55.8% vs 29.2%; P< 0.001) and albuminuria (10384.04 ng/ml vs 5845.45 ng/ml; P<0.001) compared to controls. The HFD group exhibited early stages of ORG lesions, with a predominance of mesangial matrix increase and podocyte hypertrophy (PH). These lesions correlated with differentially expressed (DE) genes and miRNAs. Functional analysis showed that four DE miRNAs in the kidneys of the HFD group negatively regulated the PTEN gene, which promotes podocyte endocytosis of lipids in ORG. Among these four miRNAs, miR-205 was upregulated in the urine of the HFD group. HFD-fed Wistar rats developed early stages of ORG, with a specific targetome of miRNAs and gene expression. The upregulation of miR-205 in the kidney and its isolation in urine are associated with lipid endocytosis in podocytes, which could become a plausible biomarker of the early stages of ORG and lead to future therapeutic research.

G-protein coupled estrogen receptor (GPER) was described to exerts several cardioprotective effects. However, the exact mechanism involved in cardiac protection remains unclear. The aim of this study is to investigate the role of GPER activation on excitation-contraction coupling (ECC), and the possibility that such effect participates in cardioprotection. Cardiac myocytes of male Wistar rats were isolated with digestive buffer and loaded with Fura-2-AM for measurement of intracellular calcium transients (CaT). Sarcomere shortening (SS) and L-type calcium current (ICaL) were also registered. Confocal technique was used to measure nitric oxide (NO) production in cells loaded with DAF-FM-diacetate. Cardiac myocytes exposed to E2 (10 nM), or G-1 (1 µM) for fifteen minutes decreased CaT, SS and ICaL. These effects were prevented using G-36 (antagonist of GPER, 1 µM), L-Name (NO synthase inhibitor, 100 nM), or wortmannin (phosphoinositide-3-kinase inhibitor, 100 nM). Moreover, G1 increased NO production, and this effect was abolished in the presence of wortmannin. We concluded that the selective activation of GPER with E2 or G1 in isolated cardiac myocytes of male rats induced a negative inotropic effect due to the reduction of ICaL and the decrease in CaT. Finally, the pathway that we proposed to be implicated in these effects is PI3K-NOS-NO.