Investigating the preventive effects of baicalin and gallocatechin against glyoxal-induced cystatin aggregation

Flavan-3-ol monomers intake is associated with osteoarthritis risk in Americans over 40 years of age: results from the National Health and Nutritional Examination Survey database

Objectives: Osteoarthritis (OA) stands as the prevailing progressive musculoskeletal disease, serving as the primary cause of chronic pain and activity limitations among adults over 40. Flavan-3-ols, common polyphenolic compounds, are believed to harbor anti-inflammatory and anti-aging properties. This study explores the relationship between flavan-3-ol intake and osteoarthritis risk in individuals over the age of 40 in the US. Methods: This study included 7452 participants over the age of 40 from three cycles (2007-2008, 2009-2010, and 2017-2018) of the National Health and Nutrition Examination Survey. Information on OA history was obtained via home surveys. Information on flavan-3-ol monomers intake was obtained using a survey from the Food and Nutrient Database for Dietary Studies. We used a logistic regression model and restricted cubic spline to analyze the relationships between flavan-3-ol monomers and OA. Stratified analyses were also conducted in this study. Results: There were 1056 participants with OA and 6396 without OA. Compared to the first tertile (T1) group, the adjusted odds ratio with a 95% confidence interval (CI) of logistic regression model 2 for the flavan-3-ol T2 group was 1.296 (0.979-1.715) (p = 0.068), the OR for (-)-epigallocatechin was 1.292 (1.025-1.629) (p = 0.032), and the OR for (-)-epicatechin 3-gallate was 1.348 (1.013, 1.793) (p = 0.042). A dose-response curve indicated a non-linear association (p for non-linearity <0.05) between OA and total flavan-3-ol monomers (nadir point: 483.29 mg, 95% CI: 0.61-0.90). No interaction effects were found in the subgroup analysis. Conclusions: In individuals over 40 in the US, the average daily dietary intake of flavan-3-ol monomers manifests a J-shaped relationship with OA risk.

Scutellaria baicalensis and its constituents baicalin and baicalein as antidotes or protective agents against chemical toxicities: a comprehensive review

Scutellaria baicalensis (SB), also known as the Chinese skullcap, has a long history of being used in Chinese medicine to treat a variety of conditions ranging from microbial infections to metabolic syndrome and malignancies. Numerous studies have reported that treatment with total SB extract or two main flavonoids found in its root and leaves, baicalin (BA) and baicalein (BE), can prevent or alleviate the detrimental toxic effects of exposure to various chemical compounds. It has been shown that BA and BE are generally behind the protective effects of SB against toxicants. This paper aimed to review the protective and therapeutic effects of SB and its main components BA and BE against chemical compounds that can cause intoxication after acute or chronic exposure and seriously affect different vital organs including the brain, heart, liver, and kidneys. In this review paper, we had a look into a total of 221 in vitro and in vivo studies from 1995 to 2021 from the scientific databases PubMed, Scopus, and Web of Science which reported protective or therapeutic effects of BA, BE, or SB against drugs and chemicals that one might be exposed to on a professional or accidental basis and compounds that are primarily used to simulate disease models. In conclusion, the protective effects of SB and its flavonoids can be mainly attributed to increase in antioxidants enzymes, inhibition of lipid peroxidation, reduction of inflammatory cytokines, and suppression of apoptosis pathway.

Fruit juices are effective anti-amyloidogenic agents

Amyloid fibril formation has been associated with a great variety of human diseases. Fruits contain different important bioactive molecules without causing various undesirable side effects, which are necessary for disease prevention and treatment. Here we report that various fruit juices inhibited the amyloid formation by α-chymotrypsin in aqueous ethanol at pH 7.0. Turbidity measurements, total phenolic content determination, as well as Congo red binding assay were used to analyse the inhibition of amyloid fibril formation. We showed that the black currant juice possessed the strongest inhibitory potential against protein aggregation because it contains the most polyphenolic compounds too and its effect was concentration dependent. Interestingly, white grapes, figs and bananas are relatively effective although they are not high in polyphenols. These fruits are typically sweet. The sugars in them also contribute to their effectiveness. Eating black currant can reduce the likelihood of formation of amyloid fibrils.

The Use of Chinese Skullcap (Scutellaria baicalensis) and Its Extracts for Sustainable Animal Production

Simple Summary

With the increasing pressure to address the problems of bacterial resistance and drug residues, medicinal herbs are gradually taking a more important role in animal production. Scutellaria baicalensis is a common and widely used Chinese medicinal herb. The main bioactive compounds in the plant are baicalein and baicalin. These compounds have many biological functions including anti-oxidation, antipyretic, analgesic, anti-inflammatory, antiallergic, antimicrobial, immunomodulatory, and antitumor effects. S. baicalensis and its extracts can effectively promote animal growth, improve the production performance of dairy cows, reduce the stress and inflammatory response, and have effective therapeutic effects on diseases caused by bacteria, viruses, and other pathogenic microorganisms. This paper summarizes the biological function of S. baicalensis and its application in sustainable animal production to provide a reference for future application of S. baicalensis and other medicinal herbs in animal production and disease treatment.

Abstract

Drugs have been widely adopted in animal production. However, drug residues and bacterial resistance are a worldwide issue, and thus the most important organizations (FAO, USDA, EU, and EFSA) have limited or banned the use of some drugs and the use of antibiotics as growth promoters. Natural products such as medicinal herbs are unlikely to cause bacterial resistance and have no chemical residues. With these advantages, medicinal herbs have long been used to treat animal diseases and improve animal performance. In recent years, there has been an increasing interest in the study of medicinal herbs. S. baicalensis is a herb with a high medicinal value. The main active compounds are baicalin and baicalein. They may act as antipyretic, analgesic, anti-inflammatory, antiallergenic, antimicrobial, and antitumor agents. They also possess characteristics of being safe, purely natural, and not prone to drug resistance. S. baicalensis and its extracts can effectively promote the production performance of livestock and treat many animal diseases, such as mastitis. In this review, we summarize the active compounds, biological functions, and applications of S. baicalensis in the production of livestock and provide a guideline for the application of natural medicines in the production and treatment of diseases.

Polyphenols as Potential Metal Chelation Compounds Against Alzheimer's Disease

Alzheimer's disease (AD) is the most common neurodegenerative disease affecting more than 50 million people worldwide. The pathology of this multifactorial disease is primarily characterized by the formation of amyloid-β (Aβ) aggregates; however, other etiological factors including metal dyshomeostasis, specifically copper (Cu), zinc (Zn), and iron (Fe), play critical role in disease progression. Because these transition metal ions are important for cellular function, their imbalance can cause oxidative stress that leads to cellular death and eventual cognitive decay. Importantly, these transition metal ions can interact with the amyloid-β protein precursor (AβPP) and Aβ42 peptide, affecting Aβ aggregation and increasing its neurotoxicity. Considering how metal dyshomeostasis may substantially contribute to AD, this review discusses polyphenols and the underlying chemical principles that may enable them to act as natural chelators. Furthermore, polyphenols have various therapeutic effects, including antioxidant activity, metal chelation, mitochondrial function, and anti-amyloidogenic activity. These combined therapeutic effects of polyphenols make them strong candidates for a moderate chelation-based therapy for AD.

Coffee extracts effectively inhibit the formation of α-chymotrypsin amyloid-like fibrils in aqueous ethanol in vitro

In this study, an in vitro α-chymotrypsin aggregation model was used to demonstrate that certain extracts of commercial coffees effectively inhibit protein aggregation in 55% ethanol at pH 7.0. To detect the anti-amyloidogenic effect of the various coffee extracts, turbidity measurements and Congo red binding assays were performed as well as the determination of the total polyphenol content of the extracts. The greatest fibril formation inhibitory effect was exerted by the Eduscho coffee extract, which contained also the most of the phenolic compounds. The Eduscho coffee extract inhibited the fibrillation of the α-chymotrypsin dose dependently. Coffee extracts are effective anti-aggregation agents, and their beneficial effects strongly correlate with the total phenolic content.

Non-enzymatic glycation of protein induces cancer cell proliferation and its inhibition by quercetin: Spectroscopic, cytotoxicity and molecular docking studies

Methylglyoxal (MG) is a potent glycating agent which reacts with proteins to form advanced glycation end products (AGEs). These chemically stable AGEs crosslink with proteins and could lead to amyloid formation that has the role in several diseases including Alzheimer's and Parkinson's. In this piece of work, glycation-induced conformational changes in HSA were observed with quenching of tryptophan fluorescence by 73.8% (41 nm red shift) and loss of hydrophobicity of HSA. CD spectroscopy result reaffirmed secondary structure changes in HSA. Moreover, MG-induced changes in HSA, proceeds to amyloid structure as characterized by an increase in thioflavin (ThT) fluorescence and transmission electron microscopy (TEM) images of HSA aggregates. Quercetin was found to inhibit both AGEs production and amyloid formation. Viability of MCF-7 cells was found to be increased with AGEs treatment, illustrating proliferation of cancer cells. Wound healing assay also revealed increased proliferation and migration of cells in the presence of AGEs. Additionally, molecular docking analyses were performed to demonstrate interactions involved in the stabilization of HSA-quercetin complex. The binding affinities of quercetin were found to be (K _d = 10⁵ M ^-1) much higher compared with MG (K _d = 10² M ^-1). From this study, it is quite clear that quercetin reverses the effect of MG by sterically inhibiting the interaction between HSA and MG. Communicated by Ramaswamy H. Sarma.