Interactions of Isoquinoline Alkaloids with Transition Metals Iron and Copper

Herbal medicines provide regulation against iron overload in cardiovascular diseases: Informing future applications

ETHNOPHARMACOLOGICAL RELEVANCE

Iron is an essential micronutrient for maintaining physiological activities, especially for highly active cardiomyocytes. Inappropriate iron overload or deficiency has a significant impact on the incidence and severity of cardiovascular diseases (CVD). Iron overload exerts potentially deleterious effects on doxorubicin (DOX) cardiomyopathy, atherosclerosis, and myocardial ischemia-reperfusion injury (MI/RI) by participating in lipid peroxides production. Notably, iron overload-associated cell death has been defined as a possible mechanism for ferroptosis. At present, some traditional herbal medicines and extracts have been included in the study of regulating iron overload and the subsequent therapeutic effect on CVD.

AIM OF THE STUDY

To give an outline of iron metabolism and ferroptosis in cardiomyocytes and to focus on herbal medicines and extracts to prevent iron overload in CVD.

MATERIALS AND METHODS

Literature information was systematically collected from ScienceDirect, PubMed, Google Scholar, Web of Science, China National Knowledge Infrastructure, WanFang data, as well as classic books and clinical reports.

RESULTS

After understanding the mechanism of iron overload on CVD, this paper reviews the therapeutic function of various herbal medicines in eliminating iron overload in CVD. These include Chinese herbal compound prescriptions (Salvia miltiorrhiza injection, Gegen Qinlian decoction, Tongxinluo, Banxia-Houpu decoction), plant extracts, phenylpropanoids, flavonoids, terpenoids, and polyphenols. Among them, flavonoids are considered to be the most promising compounds because of their prominent iron chelation. Mechanically, these herbal medicines act on the Nrf2 signaling pathway, AMPK signaling pathway, and KAT5/GPX4 signaling pathway, thereby attenuating iron overload and lipid peroxidation in CVD.

CONCLUSION

Our review provides up-to-date information on herbal medicines that exert cardiovascular protective effects by modulating iron overload and ferroptosis. These herbal medicines hold promise as a template for preventing iron overload in CVD.

Drug Selection and Posology, Optimal Therapies and Risk/Benefit Assessment in Medicine: The Paradigm of Iron-Chelating Drugs

The design of clinical protocols and the selection of drugs with appropriate posology are critical parameters for therapeutic outcomes. Optimal therapeutic protocols could ideally be designed in all diseases including for millions of patients affected by excess iron deposition (EID) toxicity based on personalised medicine parameters, as well as many variations and limitations. EID is an adverse prognostic factor for all diseases and especially for millions of chronically red-blood-cell-transfused patients. Differences in iron chelation therapy posology cause disappointing results in neurodegenerative diseases at low doses, but lifesaving outcomes in thalassemia major (TM) when using higher doses. In particular, the transformation of TM from a fatal to a chronic disease has been achieved using effective doses of oral deferiprone (L1), which improved compliance and cleared excess toxic iron from the heart associated with increased mortality in TM. Furthermore, effective L1 and L1/deferoxamine combination posology resulted in the complete elimination of EID and the maintenance of normal iron store levels in TM. The selection of effective chelation protocols has been monitored by MRI T2* diagnosis for EID levels in different organs. Millions of other iron-loaded patients with sickle cell anemia, myelodysplasia and haemopoietic stem cell transplantation, or non-iron-loaded categories with EID in different organs could also benefit from such chelation therapy advances. Drawbacks of chelation therapy include drug toxicity in some patients and also the wide use of suboptimal chelation protocols, resulting in ineffective therapies. Drug metabolic effects, and interactions with other metals, drugs and dietary molecules also affected iron chelation therapy. Drug selection and the identification of effective or optimal dose protocols are essential for positive therapeutic outcomes in the use of chelating drugs in TM and other iron-loaded and non-iron-loaded conditions, as well as general iron toxicity.

The composition, pharmacological effects, related mechanisms and drug delivery of alkaloids from Corydalis yanhusuo

Corydalis yanhusuo W. T. Wang, also known as yanhusuo, yuanhu, yanhu and xuanhu, is one of the herb components of many Chinese Traditional Medicine prescriptions such as Jin Ling Zi San and Yuanhu-Zhitong priscription. C. yanhusuo was traditionally used to relieve pain and motivate blood and Qi circulation. Now there has been growing interest in pharmacological effects of alkaloids, the main bioactive components of C. yanhusuo. Eighty-four alkaloids isolated from C. yanhusuo are its important bioactive components and can be characterized into protoberberine alkaloids, aporphine alkaloids, opiate alkaloids and others and proper extraction or co-administration methods modulate their contents and efficacy. Alkaloids from C. yanhusuo have various pharmacological effects on the nervous system, cardiovascular system, cancer and others through multiple molecular mechanisms such as modulating neurotransmitters, ion channels, gut microbiota, HPA axis and signaling pathways and are potential treatments for many diseases. Plenty of novel drug delivery methods such as autologous red blood cells, self-microemulsifying drug delivery systems, nanoparticles and others have also been investigated to better exert the effects of alkaloids from C. yanhusuo. This review summarized the alkaloid components of C. yanhusuo, their pharmacological effects and mechanisms, and methods of drug delivery to lay a foundation for future investigations.

Antioxidant Potential of Ethiopian Medicinal Plants and Their Phytochemicals: A Review of Pharmacological Evaluation

Background

Free radicals are very reactive molecules produced during oxidation events that in turn initiate a chain reaction resulting in cellular damage. Many degenerative diseases in humans, including cancer and central nervous system damage, are caused by free radicals. Scientific evidence indicates that active compounds from natural products can protect cells from free radical damage. As a result, the aim of this review is to provide evidence of the use of diverse Ethiopian medicinal plants with antioxidant properties that have been scientifically validated in order to draw attention and foster further investigations in this area.

Methods

The keywords antioxidant, radical scavenging activities, reactive oxygen species, natural product, Ethiopian Medicinal plants, and 2, 2-Diphenyl-1-picrylhydrazyl radical scavenging assay (DPPH) were used to identify relevant data in the major electronic scientific databases, including Google Scholar, ScienceDirect, PubMed, Medline, and Science domain. All articles with descriptions that were accessed until November 2022 were included in the search strategy.

Results

A total of 54 plant species from 33 families were identified, along with 46 compounds isolated. More scientific studies have been conducted on plant species from the Brassicaceae (19%), Asphodelaceae (12%), and Asteraceae (12%) families. The most used solvent and extraction method for plant samples are methanol (68%) and maceration (88%). The most examined plant parts were the leaves (42%). Plant extracts (56%) as well as isolated compounds (61%) exhibited significant antioxidant potential. The most effective plant extracts from Ethiopian flora were Bersama abyssinica, Solanecio gigas, Echinops kebericho, Verbascum sinaiticum, Apium leptophyllum, and Crinum abyssinicum. The best oxidative phytochemicals were Rutin (7), Flavan-3-ol-7-O-glucoside (8), Myricitrin (13), Myricetin-3-O-arabinopyranoside (14), 7-O-Methylaloeresin A (15), 3-Hydroxyisoagatholactone (17), β-Sitosterol-3-O-β-D-glucoside (22), Microdontin A/B (24), and Caffeic acid (39).

Conclusion

Many crude extracts and compounds exhibited significant antioxidant activity, making them excellent candidates for the development of novel drugs. However, there is a paucity of research into the mechanisms of action as well as clinical evidence supporting some of these isolated compounds. To fully authenticate and then commercialize, further investigation and systematic analysis of these antioxidant-rich species are required.

The antidiabetic effect of methanolic extract of Holarrhena pubescens seeds is mediated through multiple mechanisms of action

Holarrhena pubescens is widely used in Indian and Chinese medicine in the treatment of diabetes. The current work determined the oral hypoglycemic and antidiabetic effects of seed extract in rats. The probable mechanism of action was evaluated in-vitro by α - glucosidase inhibition, glucose metabolism in insulinoma (INS-1) cells to reflect secretion of insulin, and protein glycation inhibition. Its potential for herb-drug interaction was evaluated in the cytochrome P450 3A4 (CYP3A4) inhibition assay. The seed extract increased serum insulin levels and reduced serum blood glucose levels in the oral glucose tolerance test. It also reduced the serum glucose levels in streptozocin-induced diabetes. The extract also inhibited α -glucosidase enzyme activity and demonstrated that it can increase the secretion of insulin from INS to 1-rat insulinoma cell line cells in-vitro in a concentration-dependent manner. However, it had a very weak inhibitory effect on protein glycation and it did not affect the activity of CYP3A4. The results of the study showed that H. pubescens seed extract increases insulin secretion and inhibits glucose absorption both in-vivo and in-vitro with a weak protein glycation inhibitory effect. The herb is devoid of CYP3A4 inhibitory effect indicating that it may not have pharmacokinetic interaction with the drug metabolized by this enzyme.

A Review of Fibraurea tinctoria and Its Component, Berberine, as an Antidiabetic and Antioxidant

Diabetes mellitus is a group of metabolic disorders characterized by hyperglycemia caused by resistance to insulin action, inadequate insulin secretion, or excessive glucagon production. Numerous studies have linked diabetes mellitus and oxidative stress. People with diabetes usually exhibit high oxidative stress due to persistent and chronic hyperglycemia, which impairs the activity of the antioxidant defense system and promotes the formation of free radicals. Recently, several studies have focused on exploring natural antioxidants to improve diabetes mellitus. Fibraurea tinctoria has long been known as the native Borneo used in traditional medicine to treat diabetes. Taxonomically, this plant is part of the Menispermaceae family, widely known for producing various alkaloids. Among them are protoberberine alkaloids such as berberine. Berberine is an isoquinoline alkaloid with many pharmacological activities. Berberine is receiving considerable interest because of its antidiabetic and antioxidant activities, which are based on many biochemical pathways. Therefore, this review explores the pharmacological effects of Fibraurea tinctoria and its active constituent, berberine, against oxidative stress and diabetes, emphasizing its mechanistic aspects. This review also summarizes the pharmacokinetics and toxicity of berberine and in silico studies of berberine in several diseases and its protein targets.