Assessing the safety of an Ephedrae Herba aqueous extract in rats: A repeat dose toxicity study

Review on Processing Methods of Toxic Chinese Materia Medica and the Related Mechanisms of Action

Toxic Chinese materia medica (CMM) has both pharmacological activities and toxic effects. Based on thousands of years of experience in the application of CMMs, people have explored many practical processing methods of CMMs, also known as "Pao Zhi", to reduce/control toxicity and preserve/enhance efficacy. Toxic CMMs have been used throughout China's hospitals. Yet, the production and use of toxic CMM should be carried out in accordance with the Chinese pharmacopoeia (ChP) and the processing regulations formulated by the health administrative departments of provinces, autonomous regions, and municipalities directly under the Central Government. This paper summarizes the current understanding and awareness of toxicity and 45 toxic CMMs, the commonly used processing methods of toxic CMMs recorded in the 2020 edition of ChP, and the changes in the chemical component, toxicity, or efficacy profiles after processing. This review may provide useful information for the processing methods of toxic CMMs worldwide. We believe that with an in-depth study and understanding of toxic CMMs combined with a standardized application, the toxicity of CMMs will be predictable and controllable in the future.

Deciphering suppressive effects of Lianhua Qingwen Capsule on COVID-19 and synergistic effects of its major botanical drug pairs

The COVID-19 pandemic has resulted in excess deaths worldwide. Conventional antiviral medicines have been used to relieve the symptoms, with limited therapeutic effect. In contrast, Lianhua Qingwen Capsule is reported to exert remarkable anti-COVID-19 effect. The current review aims to: 1) uncover the main pharmacological actions of Lianhua Qingwen Capsule for managing COVID-19; 2) verify the bioactive ingredients and pharmacological actions of Lianhua Qingwen Capsule by network analysis; 3) investigate the compatibility effect of major botanical drug pairs in Lianhua Qingwen Capsule; and 4) clarify the clinical evidence and safety of the combined therapy of Lianhua Qingwen Capsule and conventional drugs. Numerous bioactive ingredients in Lianhu Qingwen, such as quercetin, naringenin, β-sitosterol, luteolin, and stigmasterol, were identified to target host cytokines, and to regulate the immune defence in response to COVID-19. Genes including androgen receptor (AR), myeloperoxidase (MPO), epidermal growth factor receptor (EGFR), insulin (INS), and aryl hydrocarbon receptor (AHR) were found to be significantly involved in the pharmacological actions of Lianhua Qingwen Capsule against COVID-19. Four botanical drug pairs in Lianhua Qingwen Capsule were shown to have synergistic effect for the treatment of COVID-19. Clinical studies demonstrated the medicinal effect of the combined use of Lianhua Qingwen Capsule and conventional drugs against COVID-19. In conclusion, the four main pharmacological mechanisms of Lianhua Qingwen Capsule for managing COVID-19 are revealed. Therapeutic effect has been noted against COVID-19 in Lianhua Qingwen Capsule.

Ephedrae Herba: A Review of Its Phytochemistry, Pharmacology, Clinical Application, and Alkaloid Toxicity

Ephedrae Herba (Ephedra), known as "MaHuang" in China, is the dried straw stem that is associated with the lung and urinary bladder meridians. At present, more than 60 species of Ephedra plants have been identified, which contain more than 100 compounds, including alkaloids, flavonoids, tannins, sugars, and organic phenolic acids. This herb has long been used to treat asthma, liver disease, skin disease, and other diseases, and has shown unique efficacy in the treatment of COVID-19 infection. Because alkaloids are the main components causing toxicity, the safety of Ephedra must be considered. However, the nonalkaloid components of Ephedra can be effectively used to replace ephedrine extracts to treat some diseases, and reasonable use can ensure the safety of Ephedra. We reviewed the phytochemistry, pharmacology, clinical application, and alkaloid toxicity of Ephedra, and describe prospects for its future development to facilitate the development of Ephedra.

Natural Sympathomimetic Drugs: From Pharmacology to Toxicology

Sympathomimetic agents are a group of chemical compounds that are able to activate the sympathetic nervous system either directly via adrenergic receptors or indirectly by increasing endogenous catecholamine levels or mimicking their intracellular signaling pathways. Compounds from this group, both used therapeutically or abused, comprise endogenous catecholamines (such as adrenaline and noradrenaline), synthetic amines (e.g., isoproterenol and dobutamine), trace amines (e.g., tyramine, tryptamine, histamine and octopamine), illicit drugs (e.g., ephedrine, cathinone, and cocaine), or even caffeine and synephrine. In addition to the effects triggered by stimulation of the sympathetic system, the discovery of trace amine associated receptors (TAARs) in humans brought new insights about their sympathomimetic pharmacology and toxicology. Although synthetic sympathomimetic agents are mostly seen as toxic, natural sympathomimetic agents are considered more complacently in the terms of safety in the vision of the lay public. Here, we aim to discuss the pharmacological and mainly toxicological aspects related to sympathomimetic natural agents, in particular of trace amines, compounds derived from plants like ephedra and khat, and finally cocaine. The main purpose of this review is to give a scientific and updated view of those agents and serve as a reminder on the safety issues of natural sympathomimetic agents most used in the community.

Interactions Between Ephedra sinica and Prunus armeniaca: From Stereoselectivity to Deamination as a Metabolic Detoxification Mechanism of Amygdalin

Mahuang–Xingren (MX, Ephedra sinica Stapf-Prunus armeniaca L.) is a classic herb pair used in traditional Chinese medicine. This combined preparation reduces the toxicity of Xingren through the stereoselective metabolism of its main active ingredient amygdalin. However, whether stereoselectivity is important in the pharmacokinetic properties of amygdalin either in the traditional decoction or in the dispensing granules is unclear. Amygdalin is hydrolyzed to its metabolite, prunasin, which produces hydrogen cyanide by degradation of the cyano group. A comprehensive study of the metabolic pathway of amygdalin is essential to better understand the detoxification process. In this article, the potential detoxification pathway of MX is further discussed with regard to herb interactions. In this study, the pharmacokinetic parameters and metabolism of amygdalin and prunasin were investigated by comparing the traditional decoction and the dispensing granule preparations. In addition, several potential metabolites were characterized in an incubation system with rat liver microsomes or gut microbial enzymes. The combination of Xingren with Mahuang reduces exposure to D-amygdalin in vivo and contributes to its detoxification, a process that can be further facilitated in the traditional decoction. From the in vitro co-incubation model, 15 metabolites were identified and classified into cyanogenesis and non-cyanogenesis metabolic pathways, and of these, 10 metabolites were described for the first time. The level of detoxified metabolites in the MX traditional decoction was higher than that in the dispensing granules. The metabolism of amygdalin by the gut microbial enzymes occurred more rapidly than that by the rat liver microsomes. These results indicated that combined boiling both herbs during the preparation of the traditional decoction may induce several chemical changes that will influence drug metabolism in vivo. The gut microbiota may play a critical role in amygdalin metabolism. In conclusion, detoxification of MX may result 1) during the preparation of the decoction, in the boiling phase, and 2) from the metabolic pathways activated in vivo. Stereoselective pharmacokinetics and deamination metabolism have been proposed as the detoxification pathway underlying the compatibility of MX. Metabolic detoxification of amygdalin was quite different between the two combinations, which indicates that the MX decoctions should not be completely replaced by their dispensing granules.

Evaluation of Acute and Subchronic Toxicity Induced by the Crude Ethanol Extract of Plukenetia volubilis Linneo Leaves in Swiss Albino Mice

Plukenetia volubilis Linneo (P. volubilis), or Sacha inca, is an oleaginous plant from the Euphorbiaceae family. The presence of terpenoids, saponins, tannins, glycosides, phytosterols, and phenolic compounds in the ethanol extracts of P. volubilis L leaves has been reported, showing a range of bioactivities including antimicrobial, anti-inflammatory, antioxidant, and analgesia. However, the safety of this plant has not yet been reported explicitly. This study thus is aimed at evaluating the toxicity of the ethanol extract of P. volubilis leaves (EtPV) by acute and subchronic toxicity tests in Swiss albino mice following standard procedures set by The Organization for Economic Cooperation and Development (OECD) with slight modifications. In the acute toxicity test, the treatment groups were administered orally with the EtPV at doses of 1000, 3000, 5000, and 7000 mg/kg body weight in small fractions during 16 hours, and the mice were then observed in 14 consecutive days. In the subchronic toxicity study, the EtPV was given at doses of 100, 300, 500, and 700 mg/kg body weight for 90 days. Changes in behavior, mortality rate, and body and the weights of vital organs, hematology, clinical biochemistry, urine analysis, and histologic morphology were evaluated. The acute toxicity study showed that the EtPV causes no sign of toxicity or mortality. The hematological, biochemical and urine analyses, changes in the weight of the body and vital organs (heart, liver and kidney), and histopathological analyses of organs indicated no evidence of toxicity at any doses. It was also revealed that oral administration of EtPV is safe at the oral doses set by acute and subchronic toxicity tests, and the oral lethal dose for the EtPV is higher than 7000 mg/kg. This study is the first to confirm the safety of P. volubilis leaf ethanol extract, and as a result, encouraging further investigation to examine EtPV potential for traditional medicine.

Effect of testosterone replacement therapy and mate tea (Ilex paraguariensis) on biochemical, functional and redox parameters of saliva in orchiectomized rats

OBJECTIVE

Evaluate the effects of testosterone replacement therapy (TRT) and mate tea (MT) [Ilex paraguariensis] on biochemical, functional, and redox parameters of saliva in orchiectomized rats (ORX) DESIGN: Sixty young adult male Wistar rats (3 months old) were either castrated bilaterally or underwent fictitious surgery (SHAM) and were distributed into 5 groups: SHAM, ORX, TU (castrated rats that received a single intramuscular injection of testosterone undecanoate 100 mg/kg), MT (castrated rats that received MT 20 mg/kg, via intragastric gavage, daily), and TU + MT. All treatments started 4 weeks after castration (4 months old) and lasted 4 weeks (5 months old). At the end of treatment, pilocarpine-induced salivary secretion was collected to analyze salivary flow rate (SFR) and biochemistry composition through determination of total protein (TP), amylase (AMY), electrolyte, and biomarkers of oxidative stress.

RESULTS

ORX increased SFR, salivary buffering capacity, calcium, phosphate, chloride, total antioxidant capacity, thiobarbituric acid reactive substances (TBARs), and carbonyl protein, reduced TP and AMY activity, and did not change pH, sodium, and potassium compared to SHAM. TU and TU+MT restored all salivary parameters to values of SHAM, while only TBARs and AMY returned to SHAM levels in the MT group.

CONCLUSIONS

TRT with long-acting TU restored the biochemical, functional, and redox parameters of saliva in orchiectomized rats. Although MT did not have a TRT-like effect on salivary gland function, the more effective reduction in lipid oxidative damage in the MT and TU + MT groups could be considered as adjuvant to alleviate the salivary oxidative stress induced by orchiectomy.

Toxicity as prime selection criterion among SARS-active herbal medications

We present here a new selection criterion for prioritizing research on efficacious drugs for the fight against COVID-19: the relative toxicity versus safety of herbal medications, which were effective against SARS in the 2002/2003 epidemic. We rank these medicines according to their toxicity versus safety as basis for preferential rapid research on their potential in the treatment of COVID-19. The data demonstrate that from toxicological information nothing speaks against immediate investigation on, followed by rapid implementation of Lonicera japonica, Morus alba, Forsythia suspensa, and Codonopsis spec. for treatment of COVID-19 patients. Glycyrrhiza spec. and Panax ginseng are ranked in second priority and ephedrine-free Herba Ephedrae extract in third priority (followed by several drugs in lower preferences). Rapid research on their efficacy in the therapy - as well as safety under the specific circumstances of COVID-19 - followed by equally rapid implementation will provide substantial advantages to Public Health including immediate availability, enlargement of medicinal possibilities, in cases where other means are not successful (non-responders), not tolerated (sensitive individuals) or just not available (as is presently the case) and thus minimize sufferings and save lives. Moreover, their moderate costs and convenient oral application are especially advantageous for underprivileged populations in developing countries.

Herb pair of Ephedrae Herba-Armeniacae Semen Amarum alleviates airway injury in asthmatic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ephedrae Herba (EH, Ephedra sinica Stapf.) and Armeniacae Semen Amarum (ASA, Prunus armeniaca L. var. ansu Maxim.) have been used to treat asthma, cold, fever, and cough in China for thousands of years.

AIM OF THE STUDY

In this study, we aimed to investigate the optimal ratio of EH and ASA compatibility (EAC) to reduce airway injury in asthmatic rats and its possible mechanism.

METHODS

Rats were sensitized with a mixture of acetylcholine chloride and histamine bisphosphate 1 h before sensitization by intragastric administration of EAC or dexamethasone or saline for 7 days. Subsequently, the ultrastructure of rat airway epithelial tissue changes, apoptosis of the airway epithelial cells, and the expression of mRNA and protein of EGRF and Bcl-2 were detected.

RESULTS

Transmission electron microscope: EAC (groups C and E) had the most prominent effect on repairing airway epithelial cells' ultrastructural changes in asthmatic rats. TUNEL: dexamethasone and EAC (groups B、C、E and F) inhibited the apoptosis of airway epithelial cells in asthmatic rats (P < 0.05). In situ hybridization: EAC (group E) inhibited the overexpression of EGFR and Bcl-2 mRNA (P < 0.05).Western Blotting: EAC (groups A、B、C、E and F) inhibited the upregulation of airway epithelial EGFR and Bcl-2 protein expression (P < 0.01).

CONCLUSIONS

Our findings indicate that EAC can inhibit abnormal changes in airway epithelial structure and apoptosis of airway epithelial cells, thereby alleviating airway injury. In this study, the best combination of EH and ASA to alleviate airway epithelial injury in asthmatic rats was group E (EH: ASA = 8: 4.5).

A Review of the Ephedra genus: Distribution, Ecology, Ethnobotany, Phytochemistry and Pharmacological Properties

Ephedra is one of the largest genera of the Ephedraceae family, which is distributed in arid and semiarid regions of the world. In the traditional medicine from several countries some species from the genus are commonly used to treat asthma, cold, flu, chills, fever, headache, nasal congestion, and cough. The chemical constituents of Ephedra species have been of research interest for decades due to their contents of ephedrine-type alkaloids and its pharmacological properties. Other chemical constituents such as phenolic and amino acid derivatives also have resulted attractive and have provided evidence-based supporting of the ethnomedical uses of the Ephedra species. In recent years, research has been expanded to explore the endophytic fungal diversity associated to Ephedra species, as well as, the chemical constituents derived from these fungi and their pharmacological bioprospecting. Two additional aspects that illustrate the chemical diversity of Ephedra genus are the chemotaxonomy approaches and the use of ephedrine-type alkaloids as building blocks in organic synthesis. American Ephedra species, especially those that exist in Mexico, are considered to lack ephedrine type alkaloids. In this sense, the phytochemical study of Mexican Ephedra species is a promising area of research to corroborate their ephedrine-type alkaloids content and, in turn, discover new chemical compounds with potential biological activity. Therefore, the present review represents a key compilation of all the relevant information for the Ephedra genus, in particular the American species, the species distribution, their ecological interactions, its ethnobotany, its phytochemistry and their pharmacological activities and toxicities, in order to promote clear directions for future research.

Acute and Chronic Toxicity of Indole Alkaloids from Leaves of Alstonia scholaris (L.) R. Br. in Mice and Rats

Alstonia scholaris (L.) R. Br. (Apocynaceae) is an evergreen tree that has been used to treat lung diseases. In this study, the toxicity profile of indole alkaloids from leaves of A. scholaris was investigated. In acute toxicity tests, mice were administered total alkaloids (TA) and five indole alkaloids. In a chronic toxicity test, rats were continuously administered TA (50, 100, and 300 mg/kg bw) for 13 weeks, followed by a 4-week recovery. A single administration of TA affected the behavior of mice, and at 12.8 g/kg bw, prone position, shortness of breath, wheezing, and convulsion were observed. The half-lethal dose (LD50) in mice was 5.48 g/kg bw, almost 2740 times the clinical dose in humans. Among the five indole alkaloids, the maximum tolerance dose in mice ranged from 0.75 to 4 g/kg bw. The TA-treated rats did not die and showed no adverse effects or dose-dependent changes in weight or food and water consumption, despite fluctuations in hematological and biochemical parameters compared with historical data. Furthermore, both gross and histopathological observations revealed no abnormalities in any organ. With daily oral administration to rats, the non-observed-adverse-effect-level of TA was 100 mg/kg bw. The results indicate that TA is safe for clinical use.

Effect of Ephedrae Herba methanol extract on high-fat diet-induced hyperlipidaemic mice

Context: Ephedrae Herba (EH), the dried stems and leaves of Ephedra sinica Stapf., E. intermedia Schrenk et C. A. Mey., or E. equisetina Bge. (Ephedraceae [Ephedra]) is used to treat respiratory diseases. Recently, especially in the Republic of Korea, EH has also been used for weight reduction. Objective: We evaluated the effects and molecular targets of methanol EH extract (EHM) on high-fat diet (HFD)-induced hyperlipidemic ICR mice. Materials and methods: EHM was orally administered (100 mg/kg body weight/day) for 3 weeks. We observed changes in body weight (BW), total cholesterol (TC), high-density lipoprotein-cholesterol, and triglycerides to evaluate the physiological changes induced by HFD or EHM administration. To evaluate lipid peroxidation and liver toxicity, malondialdehyde and blood alanine aminotransferase levels were measured. In addition to analyzing liver gene expression profiles, EHM target proteins were identified using a protein interaction database. Results: EHM administration for 3 weeks significantly (p < 0.05) decreased TC and triglyceride levels without altering BW in mice, and gene expression levels in the livers of EHM-treated mice were restored at 34.0% and 48.4% of those up- or down-regulated by hyperlipidaemia, respectively. Proteins related to DNA repair and energy metabolism were identified via protein interaction network analysis as molecular targets of EHM that play key roles in ameliorating hyperlipidaemia. Discussion and conclusions: EHM regulated hyperlipidaemia by decreasing total blood lipid and triglyceride levels in hyperlipidaemic mice. EHM showed preventive effects against hyperlipidaemia in mice, possibly via the regulation of DNA repair and the expression of energy metabolism-related genes and proteins.

Sub-chronic oral toxicity of the aqueous extract of lithospermi radix in Fischer 344 rats

ETHNOPHARMACOLOGICAL RELEVANCE

Lithospermi radix has been prescribed in traditional folk medicine to treat diverse diseases like cancer.

AIM OF THE STUDY

The present study assessed the sub-chronic oral toxicity of an aqueous extract of lithospermi radix (WLR) in Fischer 344 rats over a period of 13 weeks.

MATERIALS AND METHODS

The chemical compositions of WLR were analyzed using ultra-high performance liquid chromatography (UHPLC). WLR was daily administered to Fischer 344 rats at 0, 500, 1000, and 2000 mg/kg body weights (bw) for 13 weeks via oral gavage. Changes in mortalities, body weights, and intakes of food and water were monitored during the WLR treatment period. Urine was collected and analyzed 12 h before necropsy. Organ weights, hematological parameters, and plasma biochemical parameters were determined along with histopathological examination.

RESULTS

When compared with the normal control group, no remarkable toxic signs or parameter variations related with WLR treatment were observed in mortality, body weights, organ weights, food and water consumptions, urinalysis, hematological and plasma biochemical analyses, and histopathological examination. Mortalities observed in one male at 2000 mg/kg bw and three females at 1000 mg/kg bw were not related with WLR treatment because no gross findings of toxicity were observed in both morphological and histological examination. Some significant changes in clinical parameters or histological lesions observed in WLR-treated animals were not related with WLR treatment because the differences were marginal and did not show dose-dependent or directional changes.

CONCLUSIONS

Based on these findings, the calculated no-observed-adverse-effect-level (NOAEL) in rats was higher than 2000 mg/kg bw.

Sympathomimetic amine compounds and hepatotoxicity: Not all are alike-Key distinctions noted in a short review

Sympathomimetic amine compounds are often pooled together and incorrectly assumed to be interchangeable with respect to potential adverse effects. A brief and specific review of sympathomimetic compounds and one instance (i.e., hepatotoxicity) where these compounds have been improperly grouped together is covered. A review of the proposed mechanisms through which known hepatotoxic sympathomimetic agents (e.g., 3,4-methylenedioxymethamphetamine or MDMA, methamphetamine and amphetamine) cause liver injury, along with a corresponding review of in vitro data, interventional data, animal model studies and observational data allow for a comparison/contrast of different agents and reveals a lack of potential toxicity for some agents (e.g., pseudoephedrine, phenylephrine, ephedrine, 1,3-dimethylamylamine, phentermine) in this broad category. Data show that compounds within the broad group of sympathomimetics display divergent pharmacological and toxicological profiles and can be clearly distinguished with respect to liver injury. These data serve as a reminder to clinicians and others, that even small structural differences between molecules can lead to drastically different pharmacological/toxicological profiles and that one should not assume that all sympathomimetic agents are hepatotoxic. Such assumptions could lead to diagnostic errors and incorrect or insufficient treatment.