Natural Traditional Medicine Research Articles

Optimization of culture conditions for in vitro adventitious roots and selected flavonoids production in Boesenbergia rotunda liquid suspension culture

Boesenbergia rotunda (L.) Mansf. is one of the unique monocotyledonous perennial plant species belonging to the ginger (Zingiberaceae) family. Locally known as ‘Temu Kunci’ in Malaysia and Indonesia, this medicinal plant has been widely used in Asian dishes, particularly as a condiment or as traditional natural medicines. The important medicinal properties of B. rotunda majorly derived from flavonoids which are highly sought as pharmaceuticals. In this study, culture conditions for the growth of adventitious roots in liquid suspension cultures were optimized. The highest adventitious root production was achieved when cultured with initial inoculum density of 1.5 g and pH value at 5.8 after five weeks of culture. HPLC analysis discovered that production of valuable flavonoid compounds (pinostrobin, cardamonin and panduratin A) was significantly higher when the adventitious roots were cultured with initial inoculum density of 1.5 g whereas the initial pH medium did not significantly affect flavonoid production.

Triphala Ameliorates Nephropathy via Inhibition of TGF-β1 and Oxidative Stress in Diabetic Rats

Introduction: Advanced glycation end products, oxidative stress, and TGF-β expression play a crucial role in pathophysiology of diabetic nephropathy. Inhibition of oxidative stress and TGF-β expression by natural traditional medicines may give an economic and safe alternative treatment option. Triphala churna, a traditional medicine, has been proved to have potent antioxidant activity, and individual components of it have shown significant antidiabetic activity. Hence, the present study was designed to study the effect of Triphala churna in diabetic nephropathy in rats. Methods: Diabetes was induced in rats by administration of streptozotocin (55 mg/kg i.p.). Four weeks after induction of diabetes, the animals were treated with Triphala churna at the doses of 250, 500, and 1,000 mg/kg for next 4 weeks. Various biochemical and urine parameters such as glucose, creatinine, blood urea nitrogen (BUN), total protein, and albumin were assessed at the end of study. Creatinine clearance, BUN clearance, and glomerular filtration rate were determined. Oxidative stress parameters such as malondialdehyde, catalase, reduced glutathione, and superoxide dismutase were determined in kidney tissues. TGF-β1 expression was measured with ELISA, immunohistochemistry, and western blot techniques. Histopathology study was carried out with haemotoxylin and eosin, periodic acid-Schiff, and Masson’s trichrome staining to determine histological changes. Results: Treatment with Triphala churna significantly improved urine parameters. Triphala churna treatment also improved plasma proteins, albumin, creatinine, and BUN levels. The oxidative stress was reduced in the kidney with the treatment of Triphala churna. Histopathological studies revealed that Triphala churna reduced kidney damage. Immunohistochemistry, ELISA, and western blotting study revealed that treatment with Triphala decreased the expression of TGF-β in kidney tissues. Conclusion: From the results, it can be concluded that Triphala churna has a significant nephroprotective effect because of its capability of inhibiting oxidative stress and TGF-β in diabetes.

Cancer Knowledge and Practices Among Indigenous Women in Guatemala

PURPOSE Guatemala, a low- and middle-income country, has some of the poorest worldwide health indicators, including a high cancer incidence. We explored general cancer knowledge and breast and cervical cancer screening practices among Indigenous women in Lake Atitlán, Guatemala. METHODS We conducted 14 in-person, semistructured interviews and one focus group with 5 traditional midwives (comadronas). All participants were Mayan women from a rural community in Lake Atitlán (median age, 43.5 years; range, 18-72 years). The interviews and focus group were conducted in the participant’s preferred language, Spanish or Kaqchikel. Three coders analyzed the data using a process of inductive thematic analysis. RESULTS Participants had little knowledge and awareness about cancer in general, including screening and prevention. They associated the term cancer with death. Most had more knowledge about cervical cancer risk factors and screening compared with breast cancer. Participants voiced misinformation that breast cancer is caused by bad breast milk and that screenings for cervical cancer involve a hysterectomy. The terms uterine, ovarian, and cervical cancer were used interchangeably. None of the participants had ever been screened for breast cancer and all participants reported not knowing anyone who had been screened in the community. Some participants reported having received pap smears in the past. Major barriers reported include the cost and travel to health institutions and fear that the procedures may hurt. There was a strong preference for female doctors to conduct screenings given stigma. Participants reported experiencing discrimination and language barriers when attending hospitals. Participants mostly relied on family members and natural traditional medicine when they felt sick. Community and family support seemed to be key for health-seeking behaviors. CONCLUSION Findings highlight the lack of knowledge, limited screening practices, and numerous barriers among Mayan women in Guatemala. Efforts should focus on health promotion through educational workshops and increased accessibility to health services.

Powder production of sea cucumber (Holothuria scabra): effect of processing methods on the antioxidant activities and physico-chemical characteristics

Sea cucumber is a fishery commodity in Southeast Sulawesi that has high economic value and has long been used as traditional natural medicine. One of the active ingredients contained in sea cucumbers is antioxidants. The purpose of this study was to characterize the antioxidant activity of sea cucumber (Holothuria scabra), which were processed into powder with various processing methods. The processing methods used were smoking, steaming and microwaving. The powder were then measured its antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. Other characteristics tested were their chemical content and morphological properties with Scanning Electron Microscope (SEM). The results showed that the sea cucumber powder production with the microwaving method produced a powder that had stronger antioxidant properties compared to smoking and steaming methods. The sea cucumber powder produced with microwave method had a higher protein content, and its morphological appearance indicated more physical damage. The method of sea cucumber powder preparation with microwave appeared to be likely more efficient in time and would have a better nutritional value.

Potential Molecular Mechanisms of Plantain in the Treatment of Gout and Hyperuricemia Based on Network Pharmacology.

Background The incidence of gout and hyperuricemia is increasing year by year in the world. Plantain is a traditional natural medicine commonly used in the treatment of gout and hyperuricemia, but the molecular mechanism of its active compounds is still unclear. Based on network pharmacology, this article predicts the targets and pathways of effective components of plantain for gout and hyperuricemia and provides effective reference for clinical medication. Method Traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP) and SymMap databases were used to screen out the active compounds and their targets in plantain. GeneCards, Therapeutic Target Database (TTD), and Online Mendelian Inheritance in Man (OMIM) databases were used to find the targets corresponding to gout and hyperuricemia. Venn diagram was used to obtain the intersection targets of plantain and diseases. The interaction network of the plantain active compounds-targets-pathways-diseases was constructed by using Cytoscape 3.7.2 software. Finally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were carried out. Result Seven active compounds were identified by network pharmacological analysis, including dinatin, baicalein, baicalin, sitosterol, 6-OH-luteolin, stigmasterol, and luteolin. Plantain plays a role in gout and hyperuricemia diseases by regulating various biological processes, cellular components, and molecular functions. The core targets of plantain for treating gout are MAPK1, RELA, TNF, NFKBIA, and IFNG, and the key pathways are pathways in cancer, hypoxia-inducible factor-1 (HIF-1) signaling pathway, interleukin (IL)-17 signaling pathway, Chagas disease (American trypanosomiasis), and relaxin signaling pathway. The core targets of plantain for hyperuricemia are RELA, MAPK1, NFKBIA, CASP3, CASP8, and TNF, and the main pathways are pathways in cancer, apoptosis, hepatitis B, IL-17 signaling pathway, and toxoplasmosis. Conclusion This study explored the related targets and mechanisms of plantain for the treatment of gout and hyperuricemia from the perspective of network pharmacological analysis, reflecting the characteristics of multiple components, multiple targets, and multiple pathways, and it provides a good theoretical basis for the clinical application of plantain.

Seeing the Unseen of the Combination of Two Natural Resins, Frankincense and Myrrh: Changes in Chemical Constituents and Pharmacological Activities.

For the treatment of diseases, especially chronic diseases, traditional natural drugs have more effective therapeutic advantages because of their multi-target and multi-channel characteristics. Among many traditional natural medicines, resins frankincense and myrrh have been proven to be effective in the treatment of inflammation and cancer. In the West, frankincense and myrrh have been used as incense in religious and cultural ceremonies since ancient times; in traditional Chinese and Ayurvedic medicine, they are used mainly for the treatment of chronic diseases. The main chemical constituents of frankincense and myrrh are terpenoids and essential oils. Their common pharmacological effects are anti-inflammatory and anticancer. More interestingly, in traditional Chinese medicine, frankincense and myrrh have been combined as drug pairs in the same prescription for thousands of years, and their combination has a better therapeutic effect on diseases than a single drug. After the combination of frankincense and myrrh forms a blend, a series of changes take place in their chemical composition, such as the increase or decrease of the main active ingredients, the disappearance of native chemical components, and the emergence of new chemical components. At the same time, the pharmacological effects of the combination seem magically powerful, such as synergistic anti-inflammation, synergistic anticancer, synergistic analgesic, synergistic antibacterial, synergistic blood-activation, and so on. In this review, we summarize the latest research on the main chemical constituents and pharmacological activities of these two natural resins, along with chemical and pharmacological studies on the combination of the two.

Screening and Evaluation of Xanthine Oxidase Inhibitors from Gnetum parvifolium in China.

As a traditional natural medicine for treating many kinds of diseases, Gnetum parvifolium showed apparent inhibition on xanthine oxidase (XO). In this study, ultrafiltration combined with liquid chromatography-mass spectrometry (LC-MS) is used for the screening of XO inhibitors from Gnetum parvifolium. Their antioxidation, XO inhibition, and enzymic kinetic parameters are also determined. Finally, piceatannol (1), rhaponiticin (2), resveratrol (3), and isorhapontigenin (4) are screened out and identified as XO inhibitors from the extract of Gnetum parvifolium. Four inhibitors show better inhibition than allopurinol and good radical scavenging abilities. However, the antioxidant activities are weaker than ascorbic acid. The kinetic parameters illustrate the inhibition mode of XO by piceatannol is competitive type, while the inhibition modes for rhaponiticin, resveratrol and isorhapontigenin are uncompetitive types. In order to evaluate the difference among samples obtained in China, the amounts of four inhibitors and related activities in 20 samples are assessed and analyzed by partial least squares analysis. The results indicate piceatannol contribute the highest coefficients in three kinds of activities. Based on these findings, more comprehensive research on pharmaceutical and biochemical activities of these four XO inhibitors could be conducted in future.

Ethnopharmacological Survey of Herbal Remedies Used for the Treatment of Cancer in the Greater Casablanca-Morocco.

Medicinal plants played an important role in traditional medicine for the treatment of diseases since antiquities. The aim of the study is to carry out an ethnobotanical survey on medicinal plants used traditionally in cancer treatment in the region of Greater Casablanca-Morocco, and to enhance the traditional herbal medicine knowledge. 110 traditional healers in the study area were interviewed face to face to response a survey questionnaire including the names of plants used in cancer treatment, used parts, methods of preparation, and route of administration. Indices of Fidelity Level (FL), Use Value (UV), and Relative Frequency of Citation (RFC) were calculated to identify the most effective plants used for cancer treatment. Eight species were specified including Aristolochia baetica, Aristolochia paucinervis, Bryonia dioica, Aquilaria malaccensis, Marrubium vulgare, Lavandula maroccana, Ephedra alata, and Euphorbia resinifera belonging to 7 families. Aristolochiaceae, Aquilariaceae, and Cucurbitaceae were the most useful families in cancer treatment with high significant indices of UV, FL, and RFC with values of 1, 100%, and 1, respectively. Roots and leaves were the most commonly used plant parts. Decoction and powder mixed with honey were the frequently used method for remedies preparation. The present study showed that the people living in Morocco's economic capital are still highly dependent on traditional herbal medicine for the treatment of cancer. Therefore, it seems that herbal medicine still plays a crucial role in the primary healthcare system for the local population. During this survey, it was reported that even some plant families are highly toxic for humans like Aristolochiaceae that are frequently used in cancer treatment in the study area. As many people still rely on natural traditional medicine considering (it is safe with no side effects), so combined effort between all social categories including scientists and traditional healers should be established for involving the scientific validity of the used plants in the treatment of diseases.

Chemoinformatics Profiling of the Bioactive Fraction of Bizzy Nut

Bizzy Nut status as a traditional natural medicine resulted from its reputation as a stimulant, increasing energy and strength, staving off hunger and a multitude of biological activities such as anti‐oxidation, anti‐cancer, and prevention of certain diseases. We have developed a method for fingerprinting and quantifying the anti‐prostatic activity existing in Bizzy Nut using liquid chromatography (LC) with a diode array detector and LC‐MS. Using this method, the chemical fingerprint of Biz‐2Fr.3 extract was established, in which the separation of more than five analytes were realized in about 30 mins, and 6–8 distinctive peaks were identified by LC/MS analysis. The linearity, precision, stability, repeatability, and accuracy of the method will clearly reveal any variations of Bizzy Nut samples produced in Jamaica in different years. To provide clues to the chemical identity of bioactive peaks (Biz‐2Fr.3), we applied LC‐MS because of its sensitivity, reproducibility, speed, and versatility. Analysis of Biz‐2Fr.3 using an Agilent 6210 Quadrupole LC‐MS with an Agilent Ultra‐2 fused silica capillary MS column in the negative ion mode resulted in three major peaks with retention times of 1.1, 5.8 and 7.5 minutes. Characterization of the molecular ions in peak one revealed the presence of the analyte, with m/z ranging from 120 m/z to 445 m/z. Peaks two and three, on the other hand, contained a single molecular ion with m/z of 181. The 1H NMR spectrum of Biz‐2Fr.3 contained peaks with the following chemical shifts, in ppm, and assignments: a stretch of H between 3.5–4ppm indicating the presence of straight chains CH, CH2 or CH3. Methyl hydrogens that are bonded to oxygen (eg. ROCH3) were observed between chemical shifts between 2.9–3.6 ppm. There is a possibility of the presence of C=C (eg. R2C=CHR) due to the shift between 4.0–4.5 ppm. The absence of the chemical shift between 6–8ppm indicates the absence of any aromatic hydrogen. The LC‐MS and NMR data suggested that we have three groups of compounds in the Biz‐2Fr.3 fraction.Support or Funding InformationGrant support: U.S. Public Health Service grants R15AT006821, awarded by the National Center for Complementary and Integrative Health.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Natural Medicines Used in the Traditional Tibetan Medical System for the Treatment of Liver Diseases.

Liver disease is one of the most risk factors threatening human health. It is of great significance to find drugs that can treat liver diseases, especially for acute and chronic hepatitis, non-alcoholic fatty liver disease, and liver cancer. The search for drugs with good efficacy from traditional natural medicines has attracted more and more attention. Tibetan medicine, one of the China's traditional medical systems, has been widely used by the Tibetan people for the prevention and treatment of liver diseases for hundreds of years. The present paper summarized the natural Tibetan medicines that have been used in Tibetan traditional system of medicine to treat liver diseases by bibliographic investigation of 22 Tibetan medicine monographs and drug standards. One hundred and ninety three species including 181 plants, 7 animals, and 5 minerals were found to treat liver diseases in traditional Tibetan medicine system. The most frequently used species are Carthamus tinctorius, Brag-zhun, Swertia chirayita, Swertia mussotii, Halenia elliptica, Herpetospermum pedunculosum, and Phyllanthus emblica. Their names, families, medicinal parts, traditional uses, phytochemicals information, and pharmacological activities were described in detail. These natural medicines might be a valuable gift from the old Tibetan medicine to the world, and would be potential drug candidates for the treatment of liver diseases. Further studies are needed to prove their medicinal values in liver diseases treatment, identify bioactive compounds, elucidate the underlying mechanism of action, and clarify their side effects or toxicity with the help of modern phytochemical, pharmacological, metabonomics, and/or clinical trial methods.

Multi-target Activities of Selected Alkaloids and Terpenoids

A majority of the world’s population continues to use traditional natural medicines based on the established knowledge of local plants for the treatment of various disease states. Often the same plant is recognized having several traditional uses. For the past few decades, the idea of "one drug, one activity, one disease" has dominated drug discovery in Western medicine, the so-called “magic bullet” approach. However, this view has been transformed through the discovery of the multi-targeting of bioactive compounds, which has opened up new areas for pharmaceutical development wherein the same drug may be simultaneously approved for the treatment of different diseases. Pursuing that discovery pathway, a wide variety of natural products have been evaluated for their multiple biological characteristics, such as analgesic, anti-proliferative, anti-inflammatory, anti-bacterial and anti-oxidant effects, among others. This mini-review highlights some of the recent findings concerning multi-target bioactive, plant-derived metabolites with a special emphasis on alkaloids and terpenoids. The alkaloids selected were colchicine, capsaicin, and vincristine, while the terpenoids chosen were artemisinin, taxol (paclitaxel), and masticadienonic acid. Issues relating to the sustainability of supply, and the efficiency of future drug discovery based on network pharmacology approaches are also mentioned. Keywords: Multi-target bioactive natural compounds, alkaloids, terpenoids, anti-proliferative agents, anti-inflammatory activity, analgesic activity, sustainable medicines

Recent Update on the Role of Chinese Material Medica and Formulations in Diabetic Retinopathy.

Diabetes mellitus is one of the most frequent endocrine disorders, affecting populations worldwide. Diabetic retinopathy (DR) is the most frequent microvascular complication of diabetes in patients aged 20 and over. Major complications of DR include intraocular neovascularization, inter-retinal edema, hemorrhage, exudates and microaneurysms. Therefore, timely medical attention and prevention are required. At present, laser-assisted therapy and other operational procedures are the most common treatment for DR. However, these treatments can cause retinal damage and scarring. Also, use of the majority of traditional medicines is not supported by clinical evidence. However, due to accumulating scientific evidence, traditional natural medications may assist in delaying or preventing the progression of DR. This review focuses on evidence for the role of traditional natural medicines and their mechanisms of action and pharmacological test results in relation to the progression of DR.

Role Identification of Passiflora Incarnata Linnaeus: A Mini Review

Some species of traditional herbal medicine has a history of use, most traditional natural herbs have been used for various diseases such as diabetes, hypertension, and obesity. Among them, Passiflora incarnata L. is a traditional natural medicine, flowers as well as berries, roots, and leaves have been used as a medicine. It has been used as a natural medicine for the treatment of insomnia and anxiety for a longtime in Europe, and it has been used primarily for sedation tea in North America. Moreover, Passiflora incarnata L. is widely used anti-asthmatic, analgesic and sedation in Brazil. In other words, Passiflora incarnata L. has been used to treat a sedative, dysmenorrhea, insomnia, cancer, etc. in many countries. Present review of the plants showed a wide range of pharmacological activity in anxiolytic relax the clinical disease, such as anti-inflammatory, anxiety and antioxidant. In addition, Passiflora incarnata L. affects menopause symptoms such as vasomotor symptoms, insomnia, and depression. This review aims to provide the latest information on specific functional components of Passiflora incarnata L. especially the results of clinical trials will provide new insights into opportunities for the future development of natural medicines and doors will be used for purposes of analysis.

Acetyl-11-keto-β-boswellic acid reduces retinal angiogenesis in a mouse model of oxygen-induced retinopathy

Retinal diseases characterized by pathologic retinal angiogenesis are the leading causes of blindness worldwide. Although therapies directed toward vascular endothelial growth factor (VEGF) represent a significant step forward in the treatment of proliferative retinopathies, further improvements are needed. In the last few years, an intense research activity has focused around the use of herbal and traditional natural medicines as an alternative for slowing down the progression of proliferative retinopathies. In the present study, we investigated the antiangiogenic effects of acetyl-11-keto-β-boswellic acid (AKBA), one of the active principles derived from the plant Boswellia serrata, used in Ayurvedic systems of medicine. We studied the antiangiogenic properties of AKBA using the mouse model of oxygen-induced retinopathy (OIR), which mimics the neovascular response seen in human retinopathy of prematurity. We first evaluated the effects of subcutaneously administered AKBA on the expression/activity of proteins which are known to play a role in the OIR model. In the retina, AKBA increased expression and activity of Src homology region 2 domain-containing phosphatase 1 and reduced the phosphorylation of the transcription factor signal transducer and activator of transcription 3 (STAT3) as well as VEGF expression and VEGF receptor (VEGFR)-2 phosphorylation. Likely as a result of these effects, AKBA significantly reduced retinal neovascularization in OIR mice without affecting retinal cell survival and retinal function. Using retinal explants cultured in hypoxia and an activator of STAT3 phosphorylation, we showed that the AKBA-induced inhibition of VEGFR-2 phosphorylation is likely to be mediated by a mechanism depending on an SHP-1/STAT3/VEGF axis. In the OIR model, neovascularization results from the activation of retinal endothelial cells, therefore we evaluated whether AKBA affected the angiogenic response of human retinal microvascular endothelial cells (HRMECs). We observed that AKBA reduced proliferation, migration and tube formation in HRMECs stimulated with exogenous VEGF, while it reduced migration and tube formation in untreated HRMECs. Taken together, our results demonstrate the antiangiogenic effects of AKBA in a model of pathologic neovascularization, providing a rationale for further investigation of AKBA as a promising therapeutic agent to reduce the impact of proliferative retinopathies.

Salacinol and related analogs: new leads for type 2 diabetes therapeutic candidates from the Thai traditional natural medicine Salacia chinensis.

The antidiabetic effect of a hot water extract of stems of Salacia chinensis (SCE) was evaluated in vivo in KK-Ay mice, a typical type 2 diabetes mellitus mice model. Administration of CE-2 dietary feed containing 0.25 and/or 0.50% of SCE for three weeks to KK-Ay mice significantly suppressed the elevation of both blood glucose and HbA1c levels without significant changes in body weight or food intake. Glucose tolerance was improved by administration to KK-Ay mice for 27 days of AIN93M purified dietary feed containing 0.12% of SCE. No suppressive effect with respect to HbA1c level was observed when AIN93M/Glc dietary feed in which all digestible glucides were replaced with glucose was administered with SCE. Thus, α-glucosidase inhibitory activity approved as the mechanism of action of the antidiabetic effect of SCE by in vitro investigation was reconfirmed also in in vivo studies. Evaluation of the α-glucosidase inhibitory activity of the active constituents, salacinol (1), kotalanol (3), and neokotalanol (4), by employing human α-glucosidases revealed that these compounds inhibited them as potently (IC50 = 3.9–4.9 μM for maltase) as they inhibited rat small intestinal α-glucosidase. The principal sulfonium constituents (1–4) were highly stable in an artificial gastric juice. In addition, 1–4 were hardly absorbed from the intestine in an experiment using the in situ rat ligated intestinal loop model. The results indicate that these sulfoniums are promising leads for a new type of anti-diabetic agents.

Activation of Cell-mediated Immunity by Morinda citrifolia Fruit Extract and Its Constituents

Morinda citrifolia, commonly known as noni, is a traditional natural medicine in French Polynesia and Hawaii. Functional foods derived from M. citrifolia fruit have been marketed to help prevent diseases and promote good health. The objective of this study was to assess the effects of M. citrifolia fruit on cell-mediated immunity. In the picryl chloride-induced contact dermatitis test, M. citrifolia fruit extract (Noni-ext) inhibited the suppression of cell-mediated immunity by immunosuppressive substances isolated from freeze-dried ascites of Ehrlich carcinoma-bearing mice (EC-sup). In addition, Noni-ext inhibited reduction of IL-2 production in EC-sup-treated mice and activated natural killer cells in normal mice. These results suggest that Noni-ext has multiple effects on the recovery of cell-mediated immunity. Furthermore, we investigated the active principles of Noni-ext and identified an iridoid glycoside, deacetylasperulosidic acid. Oral administration of deacetylasperulosidic acid inhibited the reduction of ear swelling, and also cancelled the suppression of IL-2 production along with the activation of natural killer cells in the same manner as that of Noni-ext.

Management of cardiorenal metabolic syndrome in diabetes mellitus: a phytotherapeutic perspective.

Cardiorenal syndrome (CRS) is a complex disease in which the heart and kidney are simultaneously affected and their deleterious declining functions are reinforced in a feedback cycle, with an accelerated progression. Although the coexistence of kidney and heart failure in the same individual carries an extremely bad prognosis, the exact cause of deterioration and the pathophysiological mechanisms underlying the initiation and maintenance of the interaction are complex, multifactorial in nature, and poorly understood. Current therapy includes diuretics, natriuretic hormones, aquaretics (arginine vasopressin antagonists), vasodilators, and inotropes. However, large numbers of patients still develop intractable disease. Moreover, the development of resistance to many standard therapies, such as diuretics and inotropes, has led to an increasing movement toward utilization and development of novel therapies. Herbal and traditional natural medicines may complement or provide an alternative to prevent or delay the progression of CRS. This review provides an analysis of the possible mechanisms and the therapeutic potential of phytotherapeutic medicines for the amelioration of the progression of CRS.

Modulation of diabetic retinopathy pathophysiology by natural medicines through PPAR‐γ‐related pharmacology

Diabetic retinopathy (DR) is one of the most common microvascular complications of diabetes and remains a major cause of preventable blindness among adults at working age. DR involves an abnormal pathology of major retinal cells, including retinal pigment epithelium, microaneurysms, inter-retinal oedema, haemorrhage, exudates (hard exudates) and intraocular neovascularization. The biochemical mechanisms associated with hyperglycaemic-induced DR are through multifactorial processes. Peroxisome proliferator-activated receptor-γ (PPAR-γ) plays an important role in the pathogenesis of DR by inhibiting diabetes-induced retinal leukostasis and leakage. Despite DR causing eventual blindness, only a few visual or ophthalmic symptoms are observed until visual loss develops. Therefore, early medical interventions and prevention are the current management strategies. Laser photocoagulation therapy is the most common treatment. However, this therapy may cause retinal damage and scarring. Herbal and traditional natural medicines may provide an alternative to prevent or delay the progression of DR. This review provides an analysis of the therapeutic potential of herbal and traditional natural medicines or their active components for the slowdown of progression of DR and their possible mechanism through the PPAR-γ pathway.

Molluscan biological and chemical diversity: secondary metabolites and medicinal resources produced by marine molluscs

The phylum Mollusca represents an enormous diversity of species with eight distinct classes. This review provides a taxonomic breakdown of the published research on marine molluscan natural products and the medicinal products currently derived from molluscs, in order to identify priority targets and strategies for future research. Some marine gastropods and bivalves have been of great interest to natural products chemists, yielding a diversity of chemical classes and several drug leads currently in clinical trials. Molluscs also feature prominently in a broad range of traditional natural medicines, although the active ingredients in the taxa involved are typically unknown. Overall secondary metabolites have only been investigated from a tiny proportion (<1%) of molluscan species. At the class level, the number of species subject to chemical studies mirrors species richness and our relative knowledge of the biology of different taxa. The majority of molluscan natural products research is focused within one of the major groups of gastropods, the opisthobranchs (a subgroup of Heterobranchia), which are primarily comprised of soft-bodied marine molluscs. Conversely, most molluscan medicines are derived from shelled gastropods and bivalves. The complete disregard for several minor classes of molluscs is unjustified based on their evolutionary history and unique life styles, which may have led to novel pathways for secondary metabolism. The Polyplacophora, in particular, have been identified as worthy of future investigation given their use in traditional South African medicines and their abundance in littoral ecosystems. As bioactive compounds are not always constitutively expressed in molluscs, future research should be targeted towards biosynthetic organs and inducible defence reactions for specific medicinal applications. Given the lack of an acquired immune system, the use of bioactive secondary metabolites is likely to be ubiquitous throughout the Mollusca and broadening the search field may uncover interesting novel chemistry.

Comparison of alpha1-adrenergic receptor cell-membrane stationary phases prepared from expressed cell line and from rabbit hepatocytes

A G-protein-coupled receptor-cell-membrane stationary phase (CMSP) has been prepared by immobilizing cell membranes on the surface of silica, as carrier. The resulting HEK293 alpha1A adrenoceptor cell-membrane stationary phase can be used for rapid on-line chromatographic determination of potential subtype-selective alpha1-adrenoceptor ligand-binding affinities for alpha 1-adrenoceptor subtypes. The objective of the research was to study whether cell lines stably overexpressing subtype receptors could improve the sensitivity and specificity of cell-membrane chromatography (CMC) compared with use of homogenized tissue and cells in primary culture. Effects of mobile-phase ionic strength, sample concentration, and the presence of competitive agents on ligand-receptor interaction in CMSP were also evaluated. We found that cell lines stably overexpressing subtype receptors led to improved sensitivity and specificity in CMC. The technique leads to useful procedures-cell-membrane stationary phases may, for example, facilitate exploration of ligand-receptor interaction and determination of ligand-receptor binding affinity in initial screening and separation of lead compounds or active components in Chinese traditional natural medicine and herbs. This might eventually be an important contribution and an addition to our collection of techniques.