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Enhancement of Hsp70 synthesis protects common carp, Cyprinus carpio L., against lethal ammonia toxicity

Sung YY, Roberts RJ, Bossier P

J Fish Dis, 2012 Aug;35(8):563-8.
PMID: 22724455 DOI: 10.1111/j.1365-2761.2012.01397.x

Exposure to TEX-OE®, a patented extract of the prickly pear cactus (Opuntia ficus indica) containing chaperone-stimulating factor, was shown to protect common carp, Cyprinus carpio L., fingerlings against acute ammonia stress. Survival was enhanced twofold from 50% to 95% after exposure to 5.92 mg L(-1) NH(3) , a level determined in the ammonia challenge bioassay as the 1-h LD50 concentration for this species. Survival of TEX-OE®-pre-exposed fish was enhanced by 20% over non-exposed controls during lethal ammonia challenge (14.21 mg L(-1) NH(3) ). Increase in the levels of gill and muscle Hsp70 was evident in TEX-OE®-pre-exposed fish but not in the unexposed controls, indicating that application of TEX-OE® accelerated carp endogenous Hsp70 synthesis during ammonia perturbation. Protection against ammonia was correlated with Hsp70 accretion.
Fulltext A decade of sustained selection pressure on two surface sites of the VP1 protein of Enterovirus A71 suggests that immune evasion may be an indirect driver for virulence

Roberts R, Yee PTI, Mujawar S, Lahiri C, Poh CL, Gatherer D

Sci Rep, 2019 04 01;9(1):5427.
PMID: 30931960 DOI: 10.1038/s41598-019-41662-8

Enterovirus A71 (EV-A71) is an emerging pathogen in the Enterovirus A species group. EV-A71 causes hand, foot and mouth disease (HFMD), with virulent variants exhibiting polio-like acute flaccid paralysis and other central nervous system manifestations. We analysed all enterovirus A71 complete genomes with collection dates from 2008 to mid-2018. All sub-genotypes exhibit a strong molecular clock with omega (dN/dS) suggesting strong purifying selection. In sub-genotypes B5 and C4, positive selection can be detected at two surface sites on the VP1 protein, also detected in positive selection studies performed prior to 2008. Toggling of a limited repertoire of amino acids at these positively selected residues over the last decade suggests that EV-A71 may be undergoing a sustained frequency-dependent selection process for immune evasion, raising issues for vaccine development. These same sites have also been previously implicated in virus-host binding and strain-associated severity of HFMD, suggesting that immune evasion may be an indirect driver for virulence (154 words).
Fulltext Airway Relaxation Effects of Water-Soluble Sclerotial Extract From Lignosus rhinocerotis

Lee MK, Li X, Yap ACS, Cheung PCK, Tan CS, Ng ST, et al.

Front Pharmacol, 2018;9:461.
PMID: 29867469 DOI: 10.3389/fphar.2018.00461

Lignosus rhinocerotis has a long history of use by the indigenous community within East Asia to treat a range of health conditions including asthma and chronic cough. To date, there is limited scientific evidence to support its therapeutic effects in relieving these airways conditions. In this study, we examined the effects of the different molecular weight fractions [high-molecular-weight (HMW), medium-molecular-weight (MMW), and low-molecular-weight (LMW)] obtained from the cold water sclerotial extract (CWE) of L. rhinocerotis on airways patency using airway segments isolated from Sprague Dawley rat in an organ bath set-up. It is demonstrated that the HMW and MMW fractions exhibited higher efficacy in relaxing the pre-contracted airways when compared to the CWE and LMW fraction. In addition, the HMW fraction markedly supressed carbachol-, 5-hydroxytrptamine-, and calcium-induced airway contractions. CWE demonstrated a lower efficacy than the HMW fraction but it also significantly attenuated carbachol- and calcium-induced airway contractions. Results showed that the bronchorelaxation effect of CWE and fractions is mediated via blockade of extracellular Ca2+ influx. The composition analysis revealed the following parts of carbohydrate and proteins, respectively: HMW fraction: 71 and 4%; MMW fraction: 35 and 1%; and LMW fraction: 22 and 0.3%. Our results strongly suggest that the polysaccharide-protein complex or proteins found in the HMW and MMW fractions is likely to contribute to the bronchorelaxation effect of CWE.
Medicinal Mushrooms and Their Use to Strengthen Respiratory Health during and Post-COVID-19 Pandemic

Booi HN, Lee MK, Fung SY, Ng ST, Tan CS, Lim KH, et al.

Int J Med Mushrooms, 2022;24(10):1-14.
PMID: 36374826 DOI: 10.1615/IntJMedMushrooms.2022045068

COVID-19 infection has been a key threat to the public health system globally, with an estimated 248 million cases worldwide. COVID-19 patients are subject to a higher risk of developing chronic respiratory disorders that are closely associated with long-term disability, multi-morbidity, and premature mortality. Although there have been recent advancements in respiratory treatment regimens, there has also been increased interest in the use of medicinal mushrooms in bridging the unaddressed pathways of action within the treatment algorithms. In this review, we provide a collection of medicinal mushrooms that are beneficial in promoting respiratory health and potentially reducing COVID-19 symptoms in patients who are newly diagnosed and those who have recovered. While reviewing the use of immunomodulatory pathways, which have shown promising results in tackling side effects and post-COVID syndromes, we also provide insights into how the antioxidant elements present in medicinal mushrooms help to achieve the same results, especially in the prophylactic and therapeutic management of COVID-19 infection. To date, medicinal mushrooms are regarded as a functional food, which, however, need further quality, safety, and efficacy assessments. These requirements are also highlighted in the present review to promote the future development and application of medicinal mushrooms for better respiratory health.
Fulltext Evidence to support cultivated fruiting body of Ophiocordyceps sinensis (Ascomycota)'s role in relaxing airway smooth muscle

Booi HN, Pang LY, Lee MK, Fung SY, Ng CL, Ng ST, et al.

J Ethnopharmacol, 2025 Jan 10;336:118727.
PMID: 39182700 DOI: 10.1016/j.jep.2024.118727

ETHNOPHARMACOLOGICAL RELEVANCE: Ophiocordyceps sinensis (O. sinensis) is a genus of Ascomycete fungus that is endemic to the alpine meadows of the Tibetan Plateau and adjoining Himalayas. It has been used traditionally as a tonic to improve respiratory health in ancient China as well as to promote vitality and longevity. Bioactive components found in O. sinensis such as adenosine, cordycepin, 3-deoxyadenosine, L-arginine and polysaccharides have gained increasing interest in recent years due to their antioxidative and other properties, which include anti-asthmatic, antiviral, immunomodulation and improvement of general health.
AIM OF THE STUDY: This study's primary aim was to investigate the effect of a cultivated fruiting body of O. sinensis strain (OCS02®) on airways patency and the secondary focus was to investigate its effect on the lifespan of Caenorhabditis elegans.
MATERIALS AND METHODS: A cultivated strain, OCS02®, was employed and the metabolic profile of its cold-water extract (CWE) was analysed through liquid chromatography-mass spectrometry (LC-MS). Organ bath approach was used to investigate the pharmacological properties of OCS02® CWE when applied on airway tissues obtained from adult male Sprague-Dawley rats. The airway relaxation mechanisms of OCS02® CWE were explored using pharmacological tools, where the key regulators in airway relaxation and constriction were investigated. For the longevity study, age-synchronised, pos-1 RNAi-treated wild-type type Caenorhabditis elegans at the L4 stage were utilised for a lifespan assay.
RESULTS: Various glycopeptides and amino acids, particularly a high concentration of L-arginine, were identified from the LC-MS analysis. In airway tissues, OCS02® CWE induced a significantly greater concentration-dependent relaxation when compared to salbutamol. The relaxation response was significantly attenuated in the presence of NG-Nitro-L-arginine methyl ester (L-NAME), 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ) and several K+ channel blockers. The longevity effect induced by OCS02® CWE (5 mg/mL and above) was observed in C. elegans by at least 17%.
CONCLUSIONS: These findings suggest that the airway relaxation mechanisms of OCS02® CWE involved cGMP-dependent and cGMP-independent nitric oxide signalling pathways. This study provides evidence that the cultivated strain of OCS02® exhibits airway relaxation effects which supports the traditional use of its wild O. sinensis in strengthening respiratory health.