Targeting mevalonate pathway by zoledronate ameliorated pulmonary fibrosis in a rat model: Promising therapy against post-COVID-19 pulmonary fibrosis

BACKGROUND

Rho kinase (ROCK) pathway plays a critical role in post-COVID-19 pulmonary fibrosis (PCPF) and its intervention with angiotensin-converting enzyme 2 (ACE2) and vascular endothelial growth factor (VEGF) will be a potential therapeutic target.

OBJECTIVES

The present study was conducted to investigate the efficacy of zoledronate (ZA) on carbon tetrachloride (CCl4) induced pulmonary fibrosis (PF) in rats through targeting ACE2, ROCK, and VEGF signaling pathways.

METHODS

Fifty male Wistar rats were divided into five groups: control, vehicle-treated, PF, PF-ZA 50, and PF-ZA 100 groups. ZA was given in two different doses 100 and 50 μg/kg/week intraperitoneally. After anesthesia, mean arterial blood pressure (MBP) was measured. After scarification, lung coefficient was calculated. Lung levels of ACE 2, interleukin-1β (IL-1β), transforming growth factor-β (TGF-β), VEGF, glutathione (GSH), and superoxide dismutase (SOD) were measured. Expression of ROCK, phosphorylated myosin phosphatase target subunit 1 (P-MYPT1), and matrix metalloproteinase (MMP-1), along with histopathological changes and immune-histochemical staining for lung α-smooth muscle actin (α-SMA), tumor necrosis factor-alpha (TNFα), and caspase-3, were evaluated.

RESULTS

ZA significantly prevented the decrease in MBP. ZA significantly increased ACE2, GSH, and SOD and significantly decreased IL-1β, TGF-β, and VEGF in lung in comparison to PF group. ZA prevented the histopathological changes induced by CCl4. ZA inhibited lung expression of ROCK, P-MYPT1, MMP-1, α-SMA, TNFα, and caspase-3 with significant differences favoring the high dose intervention.

CONCLUSION

ZA in a dose-dependent manner prevented the pathological effect of CCl4 in the lung by targeting mevalonate pathway. It could be promising therapy against PCPF.

Vitamin D and lactoferrin attenuate stress-induced colitis in Wistar rats via enhancing AMPK expression with inhibiting mTOR-STAT3 signaling and modulating autophagy

Irritable bowel syndrome (IBS) is a global gastrointestinal disorder closely related to psychological stress exposure and local colonic inflammation. Herein, we investigated the effect of wrap-restraint stress (WRS) on rat behavior, on adenosine monophosphate-activated protein kinase-mammalian/mechanistic target of rapamycin-signal transducer and activator of transcription 3 (AMPK-mTOR-STAT3) signaling, and autophagy in colonic mucosa. The impact of chronic administration of vitamin D₃ and lactoferrin was compared. Twenty-four male Wistar rats were randomly divided into four groups. Chronic WRS protocol was applied as a rodent model of IBS. Group I: naïve animals, Group II: WRS animals, Group III: WRS-exposed and treated with vitamin D₃ (500 IU/kg/day), and Group IV: WRS-exposed and treated with lactoferrin (300 mg/kg/day). In this study, we found that chronic administration of each of vitamin D₃ and lactoferrin resulted in a significant increase in social interaction test, interleukin-10, AMPK, optical density of LC3B, goblet cell count and marked decrease in serum cortisol level, STAT3, inflammatory cell count, and optical density of mTOR in comparison to the WRS rats. Our findings suggest that both vitamin D₃ and Lactoferrin could augment colonic autophagy through enhanced AMPK expression and inhibition of mTOR-STAT3 signaling, which offers practical insights into their clinical use in the prevention and therapy of IBS. However, lactoferrin intake as a nutritional supplement could be more helpful for stress-induced colitis treatment than vitamin D_3.

Selenium and silver nanoparticles: A new approach for treatment of bacterial and viral hepatic infections via modulating oxidative stress and DNA fragmentation

Nanoparticles are recently playing a potential role in improving drug uptake and the treatment of diseases. A variety of nanoparticles, such as selenium nanoparticles (SeNPs) and silver nanoparticles (AgNPs) have been used as drug carriers in various ways for treatment of cancers and liver diseases. Our aim in this study is to investigate the ability of AgNPs and SeNPs to target and treat the viral and bacterial infection of the liver in rats and cell lines. For assessment of antioxidant activity of AgNPs in rats with induced liver bacterial infection, six adult male albino rats were included in this study, liver slices were taken and assigned to 6 groups. Markers of hepatic functions, oxidative stress, and inflammation in liver slices are carried out. Although for assessment of antiviral activity of SeNPs, hepatitis B virus transfected (HBV)-replicating human cell line HepG2 and normal hepatocyte cells were used, hepatic and inflammatory alterations are determined through quantitative polymerase chain reaction and comet assay techniques. The effect of AgNPs on interleukin-6 and tumor necrosis factor levels were reduced in different treated groups with AgNPs compared with the control and diseased groups. On the other hand, SeNPs revealed significant alterations in the inflammatory markers as well as DNA damage in the treated HBV-human cell line HepG2 compared to the diseased ones. AgNPs have the ability for producing various hepatic alterations and can inhibit the proliferation of hepatic stellate cells (HSCs) in a dose and size-dependent manner. On the other hand, SeNPs showed excellent selectivity towards viral cells in the HepG2 cell lines. Both AgNPs and SeNPs might be promising drug designs for treating viral and bacterial liver diseases.