Catalpol alleviates Ang II-induced renal injury through NF/κB pathway and TGF-β1/Smads pathway

Iridoids modulate inflammation in diabetic kidney disease: A review

In recent years, preclinical research on diabetic kidney disease (DKD) has surged to the forefront of scientific and clinical attention. DKD has become a pervasive complication of type 2 diabetes. Given the complexity of its etiology and pathological mechanisms, current interventions, including drugs, dietary modifications, exercise, hypoglycemic treatments and lipid-lowering methods, often fall short in achieving desired therapeutic outcomes. Iridoids, primarily derived from the potent components of traditional herbs, have been the subject of long-standing research. Preclinical data suggest that iridoids possess notable renal protective properties; however, there has been no summary of the research on their efficacy in the management and treatment of DKD. This article consolidates findings from in vivo and in vitro research on iridoids in the context of DKD and highlights their shared anti-inflammatory activities in treating this condition. Additionally, it explores how certain iridoid components modify their chemical structures through the regulation of intestinal flora, potentially bolstering their therapeutic effects. This review provides a focused examination of the mechanisms through which iridoids may prevent or treat DKD, offering valuable insights for future research endeavors. Please cite this article as: Zhou TY, Tian N, Li L, Yu R. Iridoids modulate inflammation in diabetic kidney disease: A review. J Integr Med. 2024; 22(3): 210-222.

Progress of research into the pharmacological effect and clinical application of the traditional Chinese medicine Rehmanniae Radix

The traditional Chinese medicine (TCM) Rehmanniae Radix (RR) refers to the fresh or dried root tuber of the plant Rehmannia glutinosa Libosch of the family Scrophulariaceae. As a traditional Chinese herbal medicine (CHM), it possesses multiple effects, including analgesia, sedation, anti-inflammation, antioxidation, anti-tumor, immunomodulation, cardiovascular and cerebrovascular regulation, and nerve damage repair, and it has been widely used in clinical practice. In recent years, scientists have extensively studied the active components and pharmacological effects of RR. Active ingredients mainly include iridoid glycosides (such as catalpol and aucuboside), phenylpropanoid glycosides (such as acteoside), other saccharides, and unsaturated fatty acids. In addition, the Chinese patent medicine (CPM) and Chinese decoction related to RR have also become major research subjects for TCM practitioners; one example is the Bolus of Six Drugs, which includes Rehmannia, Lily Bulb and Rehmannia Decoction, and Siwu Decoction. This article reviews recent literature on RR; summarizes the studies on its chemical constituents, pharmacological effects, and clinical applications; and analyzes the progress and limitations of current investigations to provide reference for further exploration and development of RR.

Anti-inflammatory effect and mechanism of catalpol in various inflammatory diseases

Catalpol is a kind of iridoid glucoside, widely found in a variety of plants, mostly extracted from the rhizome of the traditional medicinal herb rehmanniae. It has various biological activities such as anti-inflammatory, antioxidant, and antitumor. The anti-inflammatory effects of catalpol have been demonstrated in a variety of diseases, such as neurological diseases, atherosclerosis, renal diseases, respiratory diseases, digestive diseases, bone and joint diseases, eye diseases, and periodontitis. The purpose of this review is to summarize the existing literature on the anti-inflammatory effects of catalpol in a variety of inflammatory diseases over the last decade and to focus on the anti-inflammatory mechanisms of catalpol.

Review on Molecular Mechanism of Hypertensive Nephropathy

Hypertension, a prevalent chronic ailment, has the potential to impair kidney function, and thereby resulting in hypertensive nephropathy. The escalating incidence of hypertensive nephropathy attributed to the aging population in urban areas, has emerged as a prominent cause of end-stage renal disease. Nevertheless, the intricate pathogenesis of hypertensive nephropathy poses considerable obstacles in terms of precise clinical diagnosis and treatment. This paper aims to consolidate the research findings on the pathogenesis of hypertensive nephropathy by focusing on the perspective of molecular biology.

Heidihuangwan alleviates renal fibrosis in rats with 5/6 nephrectomy by inhibiting autophagy

Renal fibrosis is a common pathway for the progression of various chronic kidney diseases (CKD), and the formation and deterioration will eventually lead to end-stage renal failure, which brings a heavy medical burden to the world. HeidihuangWan (HDHW) is a herbal formulation with stable and reliable clinical efficacy in the treatment of renal fibrosis. However, the mechanism of HDHW in treating renal fibrosis is not clear. In this study, we aimed to investigate the mechanism of HDHW to improve renal fibrosis. Wistar rats were randomly divided into the normal control group, 5/6 Nephrectomy group, astragaloside IV (AS-IV) group, HDHW group, and HDHW + IGF-1R inhibitor (JB1) group. Except for the normal control group, the rat renal fibrosis model was established by 5/6 nephrectomy and intervened with drugs for 8 weeks. Blood samples were collected to evaluate renal function. Hematoxylin-Eosin (HE), Periodic Acid-Schiff (PAS), Modified Masson’s Trichrome (Masson) staining were used to evaluate the pathological renal injury, and immunohistochemistry and Western blotting were used to detect the protein expression of renal tissue. The results showed that HDHW was effective in improving renal function and reducing renal pathological damage. HDHW down-regulated the levels of fibrosis marker proteins, including α-smooth muscle actin (α-SMA), vimentin, and transforming growth factors–β(TGF-β), which in turn reduced renal fibrosis. Further studies showed that HDHW down-regulated the expression of autophagy-related proteins Beclin1 and LC3II, indicating that HDHW inhibited autophagy. In addition, we examined the activity of the class I phosphatidylinositol-3 kinase (PI3K)/serine-threonine kinase (Akt)/mTOR pathway, an important signaling pathway regulating autophagy, and the level of insulin-like growth factor 1 (IGF-1), an upstream activator of PI3K/Akt/mTOR. HDHW upregulated the expression of IGF-1 and activated the PI3K/Akt/mTOR pathway, which may be a vital pathway for its inhibition of autophagy. Application of insulin-like growth factor 1 receptor (IGF-1R) inhibitor further confirmed that the regulation of autophagy and renal fibrosis by HDHW was associated with IGF-1-mediated activation of the PI3K/Akt/mTOR pathway. In conclusion, our study showed that HDHW inhibited autophagy by upregulating IGF-1 expression, promoting the binding of IGF-1 to IGF-1R, and activating the PI3K/Akt/mTOR signaling pathway, thereby reducing renal fibrosis and protecting renal function. This study provides support for the application and further study of HDHW.