Medicinal Plants for Mitigating Pain and Inflammatory-Related Conditions: An Appraisal of Ethnobotanical Uses and Patterns in South Africa

Bioactive Molecules, Ethnomedicinal Uses, Toxicology, and Pharmacology of Peltophorum africanum Sond (Fabaceae): Systematic Review

Plants have long been used to treat serious illnesses in both humans and animals. A significant underappreciated medicinal tree, Peltophorum africanum Sond is utilized by many different ethnic groups to cure a wide range of illnesses. A variety of electronic databases, including ScienceDirect, Scopus, Scielo, Scifinder, PubMed, Web of Science, Medline, and Google Scholar, were used to search the literature on P. africanum, using key words such as uses, survey, pharmacology, antigonococcal, toxicity, phytochemistry and others. Further data was obtained from several scholarly theses, dissertations, and books on general plant sciences, ethnomedicine, and other pertinent ethnobotanical topics. The plant species possess very important pharmacological activities in vitro, which includes antimicrobial, anti-HIV, antioxidant, anticancer, antidiabetic, and other activities. Phytochemically, the plant possesses various classes of compounds, dominated by flavonols, which may well explain its wider range of pharmacological activities. Although the plant is promising anti-HIV activity, the mode of action and safety profiles of the plant also need to be explored as its extracts exerted some degree of mutagenicity. It is also important to further explore its ethnoveterinary use against a plethora of nematodes that infects both wild and domestic animals. Given its potent pharmacological activity, the further in vivo studies need to be explored to ascertain the comprehensive toxicology of the plant species, thereby developing possible medications. The plant species may further be elevated to a potent pharmaceutical product against plethora of infections.

An Evaluation of Sex-Specific Pharmacokinetics and Bioavailability of Kokusaginine: An In Vitro and In Vivo Investigation

Kokusaginine is a bioactive ingredient extracted from Ruta graveolens L., which has a range of biological activities. Its pharmacokinetic (PK) properties are particularly important for clinical applications; however, they have not been fully elucidated. In addition, the effect of sex differences on drug metabolism is increasingly being recognized, but most studies have ignored this important factor. This study aims to fill this knowledge gap by taking an in-depth look at the PK properties of kokusaginine and how gender affects its metabolism and distribution in the body. It also lays the foundation for clinical drug development. In this study, a sensitive ultra-high-performance liquid chromatography (UPLC) method was developed and validated for quantifying kokusaginine in Sprague Dawley (SD) rat plasma and tissue homogenates. Metabolic stability was evaluated in vitro using gender-specific liver microsomes. Innovatively, we incorporated sex as a variable into both in vitro and in vivo PK studies in SD rats, analyzing key parameters with Phoenix 8.3.5 software. The developed UPLC method demonstrated high sensitivity and precision, essential for PK analysis. Notably, in vitro studies revealed a pronounced sex-dependent metabolic variability (p < 0.05). In vivo, gender significantly affected the Area Under the Moment Curve (AUMC)(0-∞) of the plasma PK parameter (p < 0.05) and the AUMC(0-t) of brain tissue (p < 0.0001), underscoring the necessity of sex-specific PK assessments. The calculated absolute bioavailability of 71.13 ± 12.75% confirmed the favorable oral absorption of kokusaginine. Additionally, our innovative tissue-plasma partition coefficient (Kp) analysis highlighted a rapid and uniform tissue distribution pattern. This study presents a sex-inclusive PK evaluation of kokusaginine, offering novel insights into its metabolic profile and distribution. These findings are instrumental for informing clinical medication practices, dosage optimization, and a nuanced understanding of drug efficacy and safety in a sex-specific context.

Arthritis alleviation: unveiling the potential in Abrus precatorius macerated oil

Aim: This study endeavors to explore the anti-arthritic effects of macerated oil derived from the plant's aerial parts. Methods: The macerated oil was prepared using maceration in coconut oil, and its phytochemical composition was elucidated using GC-MS. To assess its anti-arthritic activity, in-vitro studies were conducted using various assays. Results & conclusion: The macerated oil showed better antioxidant and anti-arthritic potential by in-vitro investigations. Molecular docking studies elucidated potential binding interactions between specific constituents of the oil and critical molecular targets implicated in the pathogenesis of arthritis, further substantiating its therapeutic potential. The results demonstrated that Abrus precatorius macerated oil could ameliorate arthritis severity in a dose-dependent manner.

An Integrated Approach to the Anti-Inflammatory, Antioxidant, and Genotoxic Potential of Portuguese Traditional Preparations from the Bark of Anacardium occidentale L

Anacardium occidentale L. stem bark Traditional Herbal Preparations (AoBTHPs) are widely used in traditional medicine to treat inflammatory conditions, such as diabetes. The present study aims to evaluate the anti-inflammatory, antioxidant, and genotoxic potential of red and white Portuguese AoBTHPs. Using a carrageenan-induced rat paw edema model, a significant anti-edema effect was observed for all tested doses of white AoBTHP (40.2, 71.5, and 127.0 mg/kg) and the two highest doses of red AoB THP (71.5 and 127.0 mg/kg). The anti-edema effect of red AoBTHP's highest dose was much more effective than indomethacin 10 mg/kg, Trolox 30 mg/kg, and Tempol 30 mg/kg. In DPPH, FRAP, and TAC using the phosphomolybdenum method, both types of AoBTHPs showed similar antioxidant activity and no genotoxicity up to 5000 µg/plate in the Ames test. The LC-UV/DAD-ESI/MS fingerprint allowed the identification of gallic and protocatechuic acids as the two main marker compounds and the presence of catechin, epicatechin, epigallocatechin gallate, and ellagic acid in both AoBTHPs. The obtained results support the validation of red and white AoB and their THPs as anti-inflammatory agents and contribute to the possible development of promising new therapeutic options to treat inflammatory conditions.

Traumatic cubitus valgus consequent of distal humeral fracture: Two case studies from the Holocene Later Stone Age in southern Africa

OBJECTIVES

Distal fractures of the humerus and their complications have rarely been described or analysed in the palaeopathological literature. The objective of this study was to evaluate two cases of distal humeral fracture with associated cubitus valgus observed in two individuals from the context of the Later Stone Age (LSA) in southern Africa.

MATERIALS

Skeletal remains of two individuals. A middle-aged female radiocarbon dated to c.160 BP and a middle-aged male radiocarbon dated to c.2 300 BP.

METHODS

Remains were macroscopically and radiographically assessed for injury.

RESULTS

Both cases presented with healed antemortem injury to the right elbow attributed to possible falls. Distal humeral fracture resulted in non-union of the lateral epicondyle with extensive morphological changes to the elbow joint including an increased carrying angle. Morphological and osteoarthritic changes suggest a survival period of several years post-injury.

SIGNIFICANCE

Cubitus valgus following traumatic injury has rarely been reported amongst historic or prehistoric populations. The described injuries would have had physical and functional consequences, raising questions relating to probable care received during the healing process. The elbow injuries would have resulted in restricted motion and instability of the elbow joint, with a high likelihood of ulnar neuropathy.

LIMITATIONS

The contextual information for these individuals is limited and do not permit broader population level study.

SUGGESTIONS FOR FURTHER RESEARCH

Formal biomechanical analysis including cross-sectional geometry analysis will provide further information regarding complications and strengthen the diagnosis of ulnar neuropathy. Further research is necessary on the prevalence and complications of humeral fracture.

Morphological and molecular characterization of bacterial endophytes from Centella asiatica leaves

BACKGROUND

Endophytes are a rich source of novel, distinct, and applicable compounds of interest in agricultural, medical, cosmetic, and pharmaceutical industries. In this respect, they have been attracting growing interest in the past few years. Endophytes are defined as microorganisms such as bacteria and fungi which have a mutualistic relationship with their host plants without causing any harm to their host. In this study, we isolated and identified bacterial endophytes from Centella asiatica collected in Western Cape, South Africa.

RESULTS

Twenty bacterial endophytes were isolated from Centella asiatica and characterized by using morphological and molecular techniques. Based on molecular traits, the isolates were identified as Pseudomonas sp. strain SGM1, Pseudomonas sp. strain SGM2, Pseudomonas sp. strain SGM3, Pseudomonas sp. strain SGM4, Pseudomonas sp. strain SGM5, Pseudomonas sp. strain SGM6, Pseudomonas sp. strain SGM7, Novosphingobium sp. strain SGM8, Pseudomonas sp. strain SGM9, Pseudomonas sp. strain SGM10, Chryseobacterium sp. strain SGM11, Enterobacter sp. strain SGM12, Enterobacter sp. strain SGM13, Pseudomonas sp. strain SGM14, Enterobacter sp. strain SGM15, Enterobacter sp. strain SGM16, Agrobacterium sp. strain SGM17, Pantoea sp. strain SGM18, Paraburkholderia sp. strain SGM19, and Pseudomonas sp. strain SGM20. Pseudomonas genus was dominant with eleven isolates. Morphological trait results showed that all isolates were gram-negative rod-shaped bacteria.

CONCLUSION

According to our understanding, this study revealed the first twenty endophytic bacteria isolated from Centella asiatica growing in the Western Cape Province, South Africa. Data obtained in the current study will increase the knowledge of the already existing microbial diversity associated with Centella asiatica. Further work is needed to evaluate the antioxidant and antibacterial activities in vitro and assess the growth and medicinal compounds of the identified endophytic bacteria in a laboratory scale bioreactors.

Ethnomedicinal Information on Plants Used for the Treatment of Bone Fractures, Wounds, and Sprains in the Northern Region of the Republic of Benin

Medicinal plants are frequently used in African countries due to their importance in the treatment of various conditions. In the northern Republic of Benin, traditional healers are recognized as specialists in the treatment of fractures, wounds, and sprains. The present study was conducted to document the practices (diagnosis and materials) and traditional knowledge accumulated by healers in this region on their area of specialty. In addition, literature-based research was performed to support the usage of the most cited plants. Sixty traditional healers identified as "reference persons" from Atakora and Donga departments in the northern Republic of Benin, who specialized in the treatment of fractures, wounds, and sprains, were interviewed in their communities through a semi-structured questionnaire. Information about the practice, age of the healers, medicinal plants used in this treatment, methods of preparation, and administration were collected. Samples of the plant species were also collected, identified, and stored in the national herbarium at the University of Abomey-Calavi, the Republic of Benin. The study enabled the identification of thirty-four (34) species belonging to twenty-three (23) families. Ochna rhizomatosa and Ochna schweinfurthiana (21%) were the most quoted plants among the species, followed by Chasmanthera dependens (12.1%), Piliostigma thonningii (11.3%), and Combretum sericeum (8.1%). These plants were reported to strengthen bones, reduce inflammation, relieve pain, and promote healing in the northern part of the Republic of Benin. Besides their ability to treat fractures, wounds, and sprains, they are also used for multiple purposes in the West African subregions. According to the available literature, some of the plants will need to be investigated for their phytoconstituents and pharmacological activity to validate their ethnobotanical uses. These results confirm the need for documenting traditional knowledge since it represents an opportunity for exploring plant species with potentially good pharmacological effects, which have been barely investigated. Plants identified may constitute a significant source of bioactive compounds in the treatment of various ailments such as skin inflammation and musculoskeletal disorders. They can be further explored to justify their use in traditional Beninese medicine.

Diosgenin Exerts Analgesic Effects by Antagonizing the Selective Inhibition of Transient Receptor Potential Vanilloid 1 in a Mouse Model of Neuropathic Pain

Diosgenin is a botanical steroidal saponin with immunomodulatory, anti-inflammatory, anti-oxidative, anti-thrombotic, anti-apoptotic, anti-depressant, and anti-nociceptive effects. However, the effects of diosgenin on anti-nociception are unclear. Transient receptor potential vanilloid 1 (TRPV1) plays an important role in nociception. Therefore, we investigated whether TRPV1 antagonism mediates the anti-nociceptive effects of diosgenin. In vivo mouse experiments were performed to examine nociception-related behavior, while in vitro experiments were performed to examine calcium currents in dorsal root ganglion (DRG) and Chinese hamster ovary (CHO) cells. The duration of capsaicin-induced licking (pain behavior) was significantly reduced following oral and intraplantar administration of diosgenin, approaching levels observed in mice treated with the TRPV1 antagonist N-(4-tertiarybutylphenyl)-4-(3-cholorphyridin-2-yl) tetrahydropyrazine-1(2H)-carbox-amide. Additionally, oral administration of diosgenin blocked capsaicin-induced thermal hyperalgesia. Further, diosgenin reduced capsaicin-induced Ca²⁺ currents in a dose-dependent manner in both DRG and CHO cells. Oral administration of diosgenin also improved thermal and mechanical hyperalgesia in the sciatic nerve constriction injury-induced chronic pain model by reducing the expression of TRPV1 and inflammatory cytokines in DRG cells. Collectively, our results suggest that diosgenin exerts analgesic effects via antagonism of TRPV1 and suppression of inflammation in the DRG in a mouse model of neuropathic pain.

An Inventory of South African Medicinal Plants Used in the Management of Sexually Transmitted and Related Opportunistic Infections: An Appraisal and Some Scientific Evidence (1990-2020)

The current work is aimed at generating the first inventory of South African medicinal plants used in the treatment of sexually transmitted and related opportunistic infections associated with HIV-AIDS. This is important in assisting researchers to access a list of plant species to evaluate for potential phytocompounds, as this area of research is greatly lagging in South Africa. A total of 335 medicinal plants from 103 families have been documented in the current work. The most represented families are Fabaceae (11.64%) and Asteraceae (6.27%). Herbs constitute 36.53%, trees 32.34%, shrubs 29.04%, climbers 1.80% and parasites 0.30%. It is worrying that on the plant parts used, the roots constitute 47.18%, while leaves and stem bark yield 16.62 and 15.01%, respectively. Catharanthus roseus exhibited the highest number of citations (19), while Peltophorum africanum had 14 and both Carica papaya and Vachelia karoo had 12. In the mode of administration of the reported medicinal plant species, most of the plants are boiled and taken orally (48.22%), while other plant species are used as mouth washes (3.25%). Although there is reasonable in vitro activity of some of the plant species, validating the relevance of use, there is still a need to explore the mode of action of such plant species; isolated compounds and possible derivatives thereof are of paramount importance and need to be explored as well. Furthermore, toxicological aspects of such plant species need to be explored.

Anti-Arthritic Effect of the Hydroethanolic Root Extract of Psydrax subcordata in Rats

Background

In Ghana, decoctions of various parts of Psydrax subcordata, Bridson (Rubiaceae) are employed in the management of inflammatory conditions. However, not much scientific data is available to back such folkloric use of the plant. This study, therefore, seeks to investigate the chronic anti-inflammatory activity of hydroethanolic root extract of Psydrax subcordata (PSRE) using the adjuvant-induced arthritis model in rats.

Methods

Freund's adjuvant-induced arthritis model was used to assess the ameliorative effects of PSRE in chronic inflammation. The effect of PSRE on tissue and joint integrity in arthritis was also evaluated by histopathology and microscopy. The effect of PSRE on oxidative markers and serum transforming growth factor (TGF) beta 1 was also determined via chemical assays.

Results

Oral PSRE (30–300 mg/kg) inhibited both ipsilateral and contralateral paw arthritis when given prophylactically and therapeutically in rats. It reduced paw defect on X-ray with histologically-reduced inflammatory cells and synovial hyperplasia. Finally, PSRE significantly reduced TGF-beta 1 levels and raised antioxidants such as reduced glutathione, catalase, and superoxide dismutase levels in arthritic rats.

Conclusion

The findings show that hydroethanolic root extract of Psydrax subcordata possesses anti-inflammatory properties in rodents.

The Fight against Infection and Pain: Devil’s Claw (Harpagophytum procumbens) a Rich Source of Anti-Inflammatory Activity: 2011–2022

Harpagophytum procumbens subsp. procumbens (Burch.) DC. ex Meisn. (Sesame seed Family—Pedaliaceae) is a popular medicinal plant known as Devil’s claw. It is predominantly distributed widely over southern Africa. Its impressive reputation is embedded in its traditional uses as an indigenous herbal plant for the treatment of menstrual problems, bitter tonic, inflammation febrifuge, syphilis or even loss of appetite. A number of bioactive compounds such as terpenoids, iridoid glycosides, glycosides, and acetylated phenolic compounds have been isolated. Harpagoside and harpagide, iridoid glycosides bioactive compounds have been reported in countless phytochemical studies as potential anti-inflammatory agents as well as pain relievers. In-depth studies have associated chronic inflammation with various diseases, such as Alzheimer’s disease, obesity, rheumatoid arthritis, type 2 diabetes, cancer, and cardiovascular and pulmonary diseases. In addition, 60% of chronic disorder fatalities are due to chronic inflammatory diseases worldwide. Inflammation and pain-related disorders have attracted significant attention as leading causes of global health challenges. Articles published from 2011 to the present were obtained and reviewed in-depth to determine valuable data findings as well as knowledge gaps. Various globally recognized scientific search engines/databases including Scopus, PubMed, Google Scholar, Web of Science, and ScienceDirect were utilized to collect information and deliver evidence. Based on the literature results, there was a dramatic decrease in the number of studies conducted on the anti-inflammatory and analgesic activity of Devil’s claw, thereby presenting a potential research gap. It is also evident that currently in vivo clinical studies are needed to validate the prior massive in vitro studies, therefore delivering an ideal anti-inflammatory and analgesic agent in the form of H. procumbens products.

Anti-Nociceptive and Anti-Inflammatory Activities of the Ethyl Acetate Extract of Belamcanda chinensis (L.) Redouté in Raw 264.7 Cells in vitro and Mouse Model in vivo

Purpose

Inflammation and accompanying pain is a common global health problem that seriously affects human quality of life worldwide. Here, we aimed to investigate the anti-nociceptive and anti-inflammatory activities of the ethyl acetate extract of B. chinensis (EAEBc) along with the underlying mechanisms of action.

Methods

The in vitro anti-inflammatory activity of EAEBc was explored using an LPS-induced RAW264.7 cell inflammatory model. Nitric oxide (NO) production, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 levels were evaluated. In vivo anti-nociceptive and anti-inflammatory activities of EAEBc were assessed with the aid of classical experimental mouse models. In addition, LPS-induced biomarker contents (TNF-α, IL-1β, IL-6, NO, iNOS, and PGE2) and formalin-induced serum inflammatory factors (NO, PGE2, 5-HT, β-EP, substance P, and NE) were determined in mice.

Results

In vitro, EAEBc significantly reduced LPS-induced NO generation and suppressed the production of TNF-α, IL-1β, and IL-6 in RAW264.7 cells in a concentration-dependent manner. In vivo, EAEBc downregulated serum TNF-α, IL-1β, IL-6, NO, iNOS, and PGE2 contents in mice with LPS-induced inflammation in a dose-dependent manner. EAEBc displayed anti-inflammatory activity in carrageenan-induced paw edema and xylene ear edema tests. Intragastric administration of EAEBc at test doses of 100 and 200 mg/kg led to inhibition of nociception and capillary permeability induced by acetic acid to varying degrees. Similarly, EAEBc exerted analgesic effects in the formalin and hot plate tests. In particular, the administration of EAEBc reversed the changes in the levels of inflammatory indicators NO, PGE2, 5-HT, β-EP, substance P, and NE in a mouse model of formalin-induced pain.

Conclusion

Our findings provide considerable evidence to support the extensive application of B. chinensis in traditional medicine and demonstrate the utility of this plant species as an effective candidate for prevention or treatment of various pain and inflammation-related conditions.

Ethnobotanical Survey of Local Flora Used for Medicinal Purposes among Indigenous People in Five Areas in Lagos State, Nigeria

Traditional medicine is typically the most accessible primary healthcare for a large proportion of the people in Nigeria. However, its potential remains under-explored, especially with regards to their documentation. This research investigated and documented the use of medicinal plants in the management of various health conditions/diseases among local populations in Lagos State. This study was conducted in five (5) locations of Lagos State i.e., Alimosho, Badagry, Eti-Osa, and Epe (including Ijebu and Imota). Ethnobotanical information from 100 participants was obtained using semi-structured questionnaires. Frequency of citation (FC), relative frequency of citation (RFC), fidelity level (FL), and informant consensus factor (ICF) were used to assess the importance of plants utilised for various health conditions/diseases. We identified 183 plants from 61 plant families with the highest number (24) of plants belonging to Fabaceae. Based on the high FC, the top-five popular plants used for managing health conditions/diseases in the study areas were Mangifera indica (95%), Waltheria indica (93%), Zingiber officinale (87%), Alchornea cordifolia (83%) and Ipomoea involucrata (81%). Furthermore, Rauvolfia vomitoria, Urena lobata and Waltheria indica were recognised as the most adaptable plants, as they were used to treat five different health conditions/diseases. The most commonly used life-forms were herbs (34%) and woody species (shrubs; 30%, and trees; 22%). The most regularly used plant parts were leaves. The calculated RFC values for all medicinal plant species ranged from 0.01 to 0.95, while FL values ranged from 7.14 to 100%. We found 14 health conditions/diseases, with ICF values ranging from 0.88 to 0.95. Insomnia, insanity, convulsion, nervousness, and muscle relaxants had the lowest (ICF = 0.88) agreement, while malaria/fevers, stomach, and respiratory-related diseases had the most (ICF = 0.95) agreement. The documented therapeutic uses of the plants provide basic data for further research aimed at pharmacological and conservation studies of the most important flora existing in the study areas.

Health benefits and biological activities of spiny monkey orange (Strychnos spinosa Lam.): An African indigenous fruit tree

ETHNOPHARMACOLOGICAL RELEVANCE

Spiny monkey orange (Strychnos spinosa Lam.) is an African endemic fruit tree that is widely consumed by humans and animals for its nutritional value. In folk medicine, different parts of S. spinosa are widely used for the management of the health and well-being of humans and livestock.

AIM

We provide a critical appraisal on the ethnobotanical uses, nutritional and pytochemical as well as the biological activities of S. spinosa.

METHODS

Articles were mined from online databases such as Google Scholar, PubMed, Science Direct, SciELO and SpringerLink. We captured research outputs that aligned with the scope of the review.

RESULTS

Strychnos spinosa remains a commonly consumed fruit due to its high nutritional (e.g. carbohydrates, crude protein and fats) content and energy. In folk medicine, different parts of S. spinosa are prescribed as remedy for diverse medical conditions especially for treating malaria, diabetes, snakebites, skin-related conditions and sexually transmitted infections in humans as well as sleeping sickness in livestock. Together with essential oils, more than 25 compounds have been profiled using Gas chromatography-mass spectrometry (GC-MS), and approximately 45 compounds have been isolated and structurally elucidated using diverse spectroscopic techniques such as UV-visible, Infrared (IR), Nuclear Magnetic Resonance (NMR) and mass spectroscopy (MS). Strychnos spinosa exerts varying degrees of biological activities against different microorganisms (bacteria and fungi) and parasites (plasmodia, trypanosomes and ticks) responsible for many diseases in humans and livestock. Furthermore, low to moderate enzyme-inhibitory effects of S. spinosa extracts suggest its ability to mitigate pains, inflammations and diabetics as well as snakebite venom. Increasing evidence from the in vivo studies support the use of the plant as a popular remedy for managing diabetics in folk medicine. The low cytotoxic effect of the plant extracts against different cell lines could be an indication of its relative safety.

CONCLUSION

Strychnos spinosa exhibits various health-promoting benefits due to its diverse nutritional and phytochemical constituents. Given that the majority of the existing evidence on these aforementioned therapeutic properties and safety are in vitro-based, the clinical significance of these results remain limited.