Quercetin potentiates the hepatoprotective effect of sildenafil and/or pentoxifylline against intrahepatic cholestasis: Role of Nrf2/ARE, TLR4/NF-κB, and NLRP3/IL-1β signaling pathways

Vincamine alleviates intrahepatic cholestasis in rats through modulation of NF-kB/PDGF/klf6/PPARγ and PI3K/Akt pathways

The defect in the hepatobiliary transport system results in an impairment of bile flow, leading to accumulation of toxic compounds with subsequent liver disorders. Vincamine, a plant indole alkaloid that is utilized as a dietary supplement, has been known for its promising pharmacological activities. For the first time, the present study was planned to estimate, at the molecular level, the potentiality of vincamine against alfa-naphthyl isothiocyanate (ANIT)-induced hepatic cholestasis. Liver function tests were analyzed. Hepatic activity of SOD and levels of GSH and MDA were assessed. Hepatic contents of bax, bcl2, NF-kB, PPARγ, catalase, heme-oxygenase-1, NTCP, and BSEP were evaluated using ELISA. mRNA levels of NF-kB, IL-1β, IL-6, TNFα, PDGF, klf6, PPARγ, and P53 were examined using qRT-PCR. PI3K, Akt and cleaved caspase-3 proteins were assessed using western blotting. Histopathological analyses were performed using hematoxylin & eosin staining. ANIT-induced hepatic cholestasis elevated liver function tests, including AST, ALT, GGT, ALP, and total bilirubin. ANIT reduced the protein expression of NTCP and BSEP hepatic transporters. It induced the expression of the inflammatory genes, TNFα, IL-6, IL-1β, and PDGF, and the expression of NF-kB at the genetic and protein level and suppressed the anti-inflammatory genes, klf6 and PPARγ. Also, antioxidant markers were reduced during ANIT induction such as GSH, SOD, catalase, heme-oxygenase-1 and PI3K/Akt pathway, while MDA levels were elevated. Furthermore, the expression of P53 gene, bax and cleaved caspase 3 proteins were activated, while bcl2 was inhibited. Also, the histopathological analysis showed degeneration of hepatocytes and inflammatory cellular infiltrates. However, vincamine treatment modulated all these markers. It improved liver function tests. It inhibited the expression of NF-kB, TNFα, IL-6, IL-1β and PDGF and activated the expression of klf6 and PPARγ. Furthermore, vincamine reduced MDA levels and induced GSH, SOD, catalase, heme-oxygenase-1 and PI3K/Akt pathway. Additionally, it inhibited expression of P53 gene, bax and cleaved caspase 3 proteins. More interestingly, vincamine showed better outcomes on the hepatic histopathological analysis and improved the alterations induced by ANIT. Vincamine alleviated hepatic dysfunction during ANIT-induced intrahepatic cholestasis through its anti-inflammatory and antioxidant efficacies by the modulation of NF-kB/PDGF/klf6/PPARγ and PI3K/Akt pathways.

Necroptosis contributes to non-alcoholic fatty liver disease pathoetiology with promising diagnostic and therapeutic functions

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent type of chronic liver disease. However, the disease is underappreciated as a remarkable chronic disorder as there are rare managing strategies. Several studies have focused on determining NAFLD-caused hepatocyte death to elucidate the disease pathoetiology and suggest functional therapeutic and diagnostic options. Pyroptosis, ferroptosis, and necroptosis are the main subtypes of non-apoptotic regulated cell deaths (RCDs), each of which represents particular characteristics. Considering the complexity of the findings, the present study aimed to review these types of RCDs and their contribution to NAFLD progression, and subsequently discuss in detail the role of necroptosis in the pathoetiology, diagnosis, and treatment of the disease. The study revealed that necroptosis is involved in the occurrence of NAFLD and its progression towards steatohepatitis and cancer, hence it has potential in diagnostic and therapeutic approaches. Nevertheless, further studies are necessary.

Ursolic acid attenuates cholestasis through NRF2-mediated regulation of UGT2B7 and BSEP/MRP2

Ursolic acid (UA), a pentacyclic triterpenoid, exhibits various pharmacological actions, such as anti-inflammation, anti-tumor, anti-diabetes, heart protection, and liver protection. However, the role of nuclear factor E2-related factor 2 (NRF2)-mediated regulation of uridine diphosphate glucuronosyltransferase (UGT2B7) and bile salt export pump (BSEP)/multidrug resistance-associated protein 2 (MRP2) in UA against cholestatic liver injury has not been cleared. The purpose of this study is to explore the effect of UA on cholestatic liver injury and its potential mechanism. The results of the liver pathology sections and blood biochemical indices demonstrated that UA significantly attenuated the cholestatic liver injury induced by alpha-naphthylisothiocyanate (ANIT) in a dose-dependent manner. The mRNA and protein levels of UGT2B7 and BSEP/MRP2 were remarkably increased in the liver of ANIT rats and HepG2 cells pretreated with UA, but this activation was suppressed with NRF2 silenced. In conclusion, our findings demonstrate that UA prevents cholestasis, which may be associated with NRF2-mediated regulation of UGT2B7, BSEP/MRP2.

Modulating Nrf-2/HO-1, apoptosis and oxidative stress signaling pathways by gabapentin ameliorates sepsis-induced acute kidney injury

PURPOSE

Globally, sepsis, which is a major health issue resulting from severe infection-induced inflammation, is the fifth biggest cause of death. This research aimed to evaluate, for the first time, the molecular effects of gabapentin's possible nephroprotective potential on septic rats by cecal ligation and puncture (CLP).

METHODS

Sepsis was produced by CLP in male Wistar rats. Evaluations of histopathology and renal function were conducted. MDA, SOD, GSH, TNF-α, IL-1β, and IL-6 levels were measured. qRT-PCR was utilized to determine the expression of Bax, Bcl-2, and NF-kB genes. The expression of Nrf-2 and HO-1 proteins was examined by western blotting.

RESULTS

CLP caused acute renal damage, elevated the blood levels of creatinine, BUN, TNF-α, IL-1β, and IL-6, reduced the expression of Nrf-2 and HO-1 proteins and the Bcl-2 gene expression, and upregulated NF-kB and Bax genes. Nevertheless, gabapentin dramatically diminished the degree of the biochemical, molecular, and histopathological alterations generated by CLP. Gabapentin reduced the levels of proinflammatory mediators and MDA, improved renal content of GSH and SOD, raised the expression of Nrf-2 and HO-1 proteins and Bcl-2 gene, and reduced the renal expression of NF-kB and Bax genes.

CONCLUSION

Gabapentin mitigated the CLP-induced sepsis-related acute kidney injury through up-regulating Nrf-2/HO-1 pathway, repressing apoptosis, and attenuating the oxidative stress status by reducing the levels of the proinflammatory mediators and enhancing the antioxidant status.

Quercetin inhibits caspase-1-dependent macrophage pyroptosis in experimental folic acid nephropathy

BACKGROUND

The role of pyroptosis in kidney disease is limited and incomplete. Quercetin, a flavonoid compound present in a variety of fruits, vegetables, and plants, has shown antioxidant and anti-inflammatory properties. This study was designed to validate the importance of pyroptosis in an experimental model of folic acid nephropathy and to explore the effect of quercetin in protecting against pyroptosis.

METHODS

Gene set enrichment analysis (GSEA) and weighted gene co-expression network analysis (WGCNA) were used to establish the correlation between pyroptosis and folic acid nephropathy. Immune cell infiltration, network pharmacology and single-cell RNA sequencing analysis were utilized to ascertain the specific target of quercetin in relation to pyroptosis. Finally, quercetin's role was verified in vivo and in vitro.

RESULTS

The GSEA analysis revealed a significant correlation between pyroptosis and folic acid nephropathy (NES = 1.764, P = 0.004). The hub genes identified through WGCNA were closely associated with inflammation. Molecular docking demonstrated a strong binding affinity between quercetin and caspase-1, a protein known to be involved in macrophage function, as confirmed by immune cell infiltration and single-cell analysis. Quercetin demonstrated a significant amelioration of kidney injury and reduction in macrophage infiltration in the animal model. Furthermore, quercetin exhibited a significant inhibition of caspase-1 expression, subsequently leading to the inhibition of pro-inflammatory cytokines expression, such as IL-1β, IL-18, TNF-α, and IL-6. The inhibitory effect of quercetin on macrophage pyroptosis was also confirmed in RAW264.7 cells.

CONCLUSION

This study contributes substantial evidence to support the significant role of pyroptosis in the development of folic acid nephropathy, and highlights the ability of quercetin to downregulate caspase-1 in macrophages as a protective mechanism against pyroptosis.

LCZ696 attenuates sepsis-induced liver dysfunction in rats; the role of oxidative stress, apoptosis, and JNK1/2-P38 signaling pathways

AIM

Sepsis is a serious inflammatory response to infection with an annual incidence rate of >48 million cases and 11 million fatalities worldwide. Furthermore, sepsis remains the world's fifth-greatest cause of death. For the first time, the current study aims to evaluate the possible hepatoprotective benefits of LCZ696, a combination of an angiotensin receptor blocker (valsartan) and a neprilysin inhibitor prodrug (sacubitril), on cecal ligation and puncture (CLP)-induced sepsis in rats.

MAIN METHODS

CLP was employed to induce sepsis. Hepatic malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), interleukin-6 (IL-6), IL-1β, tumor necrosis factor-alpha (TNF-α), and caspase 3 were assessed using ELISA. Serum alanine transaminase (ALT) and aspartate transaminase (AST) were also measured. Western blot assay was used to determine the expression of JNK1/2 and P38 proteins. The histology of liver tissues was also examined.

KEY FINDINGS

CLP resulted in significant elevation of AST, ALT, MDA, IL-6, IL-1β, TNF-α, and caspase 3 levels, and up-regulation of p/t JNK1/2, and p/t P38 proteins, as compared to the sham group. However, level of GSH, and SOD activity were reduced in CLP group. LCZ696 significantly improved all the previously mentioned biochemical and histological abnormalities better than using valsartan alone.

SIGNIFICANCE

LCZ696 substantially ameliorated CLP-induced liver damage, compared to valsartan, by reducing proinflammatory mediators, inhibiting the JNK1/2 and P38 signaling pathway, and attenuating apoptosis.

Vincamine Ameliorates Epithelial-Mesenchymal Transition in Bleomycin-Induced Pulmonary Fibrosis in Rats; Targeting TGF-β/MAPK/Snai1 Pathway

Idiopathic pulmonary fibrosis is a progressive, irreversible lung disease that leads to respiratory failure and death. Vincamine is an indole alkaloid obtained from the leaves of Vinca minor and acts as a vasodilator. The present study aims to investigate the protective activity of vincamine against EMT in bleomycin (BLM)-induced pulmonary fibrosis via assessing the apoptotic and TGF-β1/p38 MAPK/ERK1/2 signaling pathways. In bronchoalveolar lavage fluid, protein content, total cell count, and LDH activity were evaluated. N-cadherin, fibronectin, collagen, SOD, GPX, and MDA levels were determined in lung tissue using ELISA. Bax, p53, bcl2, TWIST, Snai1, and Slug mRNA levels were examined using qRT-PCR. Western blotting was used to assess the expression of TGF-β1, p38 MAPK, ERK1/2, and cleaved caspase 3 proteins. H & E and Masson's trichrome staining were used to analyze histopathology. In BLM-induced pulmonary fibrosis, vincamine reduced LDH activity, total protein content, and total and differential cell count. SOD and GPX were also increased following vincamine treatment, while MDA levels were decreased. Additionally, vincamine suppressed the expression of p53, Bax, TWIST, Snail, and Slug genes as well as the expression of factors such as TGF-β1, p/t p38 MAPK, p/t ERK1/2, and cleaved caspase 3 proteins, and, at the same time, vincamine increased bcl2 gene expression. Moreover, vincamine restored fibronectin, N-Catherine, and collagen protein elevation due to BLM-induced lung fibrosis. In addition, the histopathological examination of lung tissues revealed that vincamine attenuated the fibrotic and inflammatory conditions. In conclusion, vincamine suppressed bleomycin-induced EMT by attenuating TGF-β1/p38 MAPK/ERK1/2/TWIST/Snai1/Slug/fibronectin/N-cadherin pathway. Moreover, it exerted anti-apoptotic activity in bleomycin-induced pulmonary fibrosis.

Green-step assembly of the supramolecular amphiphile constructed by sodium carboxymethyl cellulose and calixarene for facile loading of hydrophobic food bioactive compounds

The use of biologically active compounds is often limited due to their poor aqueous solubility, which generally reduces their bioavailability and useful efficacy. In this regard, a wide search is currently underway for colloidal systems capable of encapsulating these compounds. In the creation of colloidal systems, long-chain molecules of surfactants and polymers are mainly used, which in an individual state do not always aggregate into homogeneous and stable nanoparticles. In the present work, cavity-bearing calixarene was used for the first time to order polymeric molecules of sodium carboxymethyl cellulose. A set of physicochemical methods demonstrated the spontaneous formation of spherical nanoparticles by non-covalent self-assembly contributed by macrocycle and polymer, and formed nanoparticles were able to encapsulate hydrophobic quercetin and oleic acid. The preparation of nanoparticles by supramolecular self-assembly without use of organic solvents, temperature and ultrasound effects can be an effective strategy for creating water-soluble forms of lipophilic bioactive compounds.

Pharmacological Activity of Flavonoid Quercetin and Its Therapeutic Potential in Testicular Injury

Quercetin is a natural flavonoid widely found in natural fruits and vegetables. Recent studies have shown that quercetin mediates multiple beneficial effects in a variety of organ damage and diseases, and is considered a healthcare supplement with health-promoting potential. Male infertility is a major health concern, and testicular damage from multiple causes is an important etiology. Previous studies have shown that quercetin has a protective effect on reproductive function. This may be related to the antioxidant, anti-inflammatory, and anti-apoptotic biological activities of quercetin. Therefore, this paper reviews the mechanisms by which quercetin exerts its pharmacological activity and its role in testicular damage induced by various etiologies. In addition, this paper compiles the application of quercetin in clinical trials, demonstrating its practical effects in regulating blood pressure and inhibiting cellular senescence in human patients. However, more in-depth experimental studies and clinical trials are needed to confirm the true value of quercetin for the prevention and protection against testicular injury.

Hepatoprotective potential of gabapentin in cecal ligation and puncture-induced sepsis; targeting oxidative stress, apoptosis, and NF-kB/MAPK signaling pathways

AIMS

Sepsis is a severe inflammatory response to infection with an incidence rate exceeding 48 million cases and 11 million sepsis-related deaths yearly. Furthermore, sepsis remains the fifth most common cause of death worldwide. The present study aimed to examine, for the first time, the potential hepatoprotective activity of gabapentin on cecal ligation and puncture (CLP)-induced sepsis in rats at the molecular level.

MAIN METHODS

CLP was used as a model of sepsis in male Wistar rats. Histological examination and liver functions were evaluated. Levels of MDA, GSH, SOD, IL-6, IL-1β, and TNF-α were investigated using ELISA. mRNA levels of Bax, Bcl-2, and NF-kB were assessed by qRT-PCR. Western blotting investigated the expression of ERK1/2, JNK1/2, and cleaved caspase 3 proteins.

KEY FINDINGS

CLP resulted in liver damage, elevated serum levels of ALT, AST, ALP, MDA, TNF-α, IL-6, and IL-1β, increased expression of ERK1/2, JNK1/2, and cleaved caspase 3 proteins, and upregulated Bax and NF-κB genes expression while it down-regulated Bcl-2 gene expression. However, gabapentin treatment significantly reduced the severity of CLP-induced biochemical, molecular, and histopathological changes. Gabapentin attenuated the levels of the proinflammatory mediators, decreased the expression of JNK1/2, ERK1/2, and cleaved caspase 3 proteins, suppressed Bax and NF-κB genes expression and increased the expression of the Bcl-2 gene.

SIGNIFICANCE

Consequently, Gabapentin reduced hepatic injury resulting from CLP-induced sepsis by reducing proinflammatory mediators, attenuating apoptosis, and inhibiting the intracellular MAPK (ERK1/2, JNK1/2)-NF-kB signaling pathway.