A Mechanism for the Treatment of Cardiovascular and Renal Disease: TRPV1 and TRPA1.

ABSTRACT: Cardiovascular disease (CVD) is the leading cause of morbidity and mortality globally. CVD and kidney disease are closely related, with kidney injury increasing CVD mortality. The pathogenesis of cardiovascular and renal diseases involves complex and diverse interactions between multiple extracellular and intracellular signaling molecules, among which transient receptor potential vanilloid 1 (TRPV1)/transient receptor potential ankyrin 1 (TRPA1) channels have received increasing attention. TRPV1 belongs to the vanilloid receptor subtype family of transient receptor potential ion channels, and TRPA1 belongs to the transient receptor potential channel superfamily. TRPV1/TRPA1 are jointly involved in the management of cardiovascular and renal diseases and play important roles in regulating vascular tension, promoting angiogenesis, antifibrosis, anti-inflammation, and antioxidation. The mechanism of TRPV1/TRPA1 is mainly related to regulation of intracellular calcium influx and release of nitric oxide and calcitonin gene-related peptide. Therefore, this study takes the TRPV1/TRPA1 channel as the research object, analyzes and summarizes the process and mechanism of TRPV1/TRPA1 affecting cardiovascular and renal diseases, and lays a foundation for the treatment of cardiorenal diseases.

Pyruvate cycle increases aminoglycoside efficacy and provides respiratory energy in bacteria.

The emergence and ongoing spread of multidrug-resistant bacteria puts humans and other species at risk for potentially lethal infections. Thus, novel antibiotics or alternative approaches are needed to target drug-resistant bacteria, and metabolic modulation has been documented to improve antibiotic efficacy, but the relevant metabolic mechanisms require more studies. Here, we show that glutamate potentiates aminoglycoside antibiotics, resulting in improved elimination of antibiotic-resistant pathogens. When exploring the metabolic flux of glutamate, it was found that the enzymes that link the phosphoenolpyruvate (PEP)-pyruvate-AcCoA pathway to the TCA cycle were key players in this increased efficacy. Together, the PEP-pyruvate-AcCoA pathway and TCA cycle can be considered the pyruvate cycle (P cycle). Our results show that inhibition or gene depletion of the enzymes in the P cycle shut down the TCA cycle even in the presence of excess carbon sources, and that the P cycle operates routinely as a general mechanism for energy production and regulation in Escherichia coli and Edwardsiella tarda These findings address metabolic mechanisms of metabolite-induced potentiation and fundamental questions about bacterial biochemistry and energy metabolism.

Two New Dolabrane Diterpenes from the Chinese Mangrove Ceriops tagal.

Two new dolabrane diterpenes, tagalenes J and K (1 and 2), together with eleven known analogues (3 - 13), were isolated from the ethanolic extract of the Chinese mangrove Ceriops tagal. The structures of these compounds were determined by extensive spectroscopic analysis, including 1D-, 2D-NMR and HR-ESI-MS, as well as the comparison with data in the literatures. Cytotoxicities of isolated compounds against MCF-7, SW480, HepG2, HeLa, PANC-1, and A2058 cancer cell lines were also evaluated. Compound 4 exhibited weak cytotoxic activity against SW480, HeLa, and PANC-1 cell lines with IC50 values of 27.7, 22.2, and 17.6 µm, respectively.

Metabolic Mechanism for l-Leucine-Induced Metabolome To Eliminate Streptococcus iniae.

Crucial metabolites that modulate hosts' metabolome to eliminate bacterial pathogens have been documented, but the metabolic mechanisms are largely unknown. The present study explores the metabolic mechanism for l-leucine-induced metabolome to eliminate Streptococcus iniae in tilapia. GC-MS-based metabolomics was used to investigate the tilapia liver metabolic profile in the presence of exogenous l-leucine. Thirty-seven metabolites of differential abundance were determined, and 11 metabolic pathways were enriched. Pattern recognition analysis identified serine and proline as crucial metabolites, which are the two metabolites identified in survived tilapias during S. iniae infection, suggesting that the two metabolites play crucial roles in l-leucine-induced elimination of the pathogen by the host. Exogenous l-serine reduces the mortality of tilapias infected by S. iniae, providing a robust proof supporting the conclusion. Furthermore, exogenous l-serine elevates expression of genes IL-1ß and IL-8 in tilapia spleen, but not TNFα, CXCR4 and Mx, suggesting that the metabolite promotes a phagocytosis role of macrophages, which is consistent with the finding that l-leucine promotes macrophages to kill both Gram-positive and Gram-negative bacterial pathogens. Therefore, the ability of phagocytosis enhanced by exogenous l-leucine is partly attributed to elevation of l-serine. These results demonstrate a metabolic mechanism by which exogenous l-leucine modulates tilapias' metabolome to enhance innate immunity and eliminate pathogens.

GC-MS-Based Metabolome and Metabolite Regulation in Serum-Resistant Streptococcus agalactiae.

Streptococcus agalactiae causes severe systemic infections in human and fish. In the present study, we established a pathogen-plasma interaction model by which we explored how S. agalactiae evaded serum-mediated killing. We found that S. agalactiae grew faster in the presence of yellow grouper plasma than in the absence of the plasma, indicating S. agalactiae evolved a way of evading the fish immune system. To determine the events underlying this phenotype, we applied GC-MS-based metabolomics approaches to identify differential metabolomes between S. agalactiae cultured with and without yellow grouper plasma. Through bioinformatics analysis, decreased malic acid and increased adenosine were identified as the most crucial metabolites that distinguish the two groups. Meanwhile, they presented with decreased TCA cycle and elevated purine metabolism, respectively. Finally, exogenous malic acid and adenosine were used to reprogram the plasma-resistant metabolome, leading to elevated and decreased susceptibility to the plasma, respectively. Therefore, our findings reveal for the first time that S. agalactiae utilizes a metabolic trick to respond to plasma killing as a result of serum resistance, which may be reverted or enhanced by exogenous malic acid and adenosine, respectively, suggesting that the metabolic trick can be regulated by metabolites.

Limonoids with an oxygen bridge between C(1) and C(29) from the seeds of a Krishna mangrove, Xylocarpus granatum.

Ten limonoids, named granatumins L-U (1-10, resp.), were isolated from the seeds of an Indian mangrove, Xylocarpus granatum, collected in the estuary of Krishna, Andhra Pradesh. The structures of these compounds were established on the basis of spectroscopic data. The relative configuration of granatumin L (1) was confirmed by a single-crystal X-ray diffraction analysis. Granatumins L-T (1-9, resp.) belong to the small group of limonoids with an oxygen bridge between C(1) and C(29), while granatumin U (10) is a 28-Me-oxidized mexicanolide. This is the first report of limonoids with an O-bridge between C(1) and C(29) from the Indian X. granatum. The pronounced structural diversity of limonoids from this mangrove might originate from environmental factors.

Decandrinin, an unprecedented C9-spiro-fused 7,8-seco-ent-abietane from the Godavari mangrove Ceriops decandra.

Decandrinin (1), an unprecedented C9-spiro-fused 7,8-seco-ent-abietane, was obtained from the bark of an Indian mangrove, Ceriops decandra, collected in the estuary of Godavari, Andhra Pradesh. The constitution and the relative configuration of 1 were determined by HRMS (ESI) and extensive NMR investigations, and the absolute configuration by circular dichroism (CD) and optical-rotatory dispersion (ORD) spectroscopy in combination with quantum-chemical calculations. Decandrinin is the first 7,8-seco-ent-abietane.

New diterpenes from a Godavari mangrove, Ceriops decandra.

Eleven new diterpenes, named decandrins A-K (1-11), including nine abietanes (1-9) and two podocarpanes (10-11), were isolated from the barks of an Indian mangrove, Ceriops decandra, collected in the mangrove swamp of Godavari estuary, Andhra Pradesh, together with four known abietanes. The structures of these compounds were established on the basis of spectroscopic data (new compounds) or comparison with data in the literature (known compounds). This is the first report of abietane and podocarpane diterpenoids from C. decandra.

New limonoids from the seeds of a Krishna mangrove, Xylocarpus granatum.

Two new mexicanolides, named granatumins H and I (1 and 2, resp.), and two phragmalins, named granatumins J and K (3 and 4, resp.), were isolated from the seeds of an Indian mangrove, Xylocarpus moluccensis, collected from the swamps of Krishna estuary, Andhra Pradesh. The structures of these limonoids were established on the basis of spectroscopic data. Granatumin J (3) is a highly oxidized phragmalin with five AcO groups, whereas granatumin K (4) is the first phragmalin found in nature with conjugated C(8)C(30) and C(14)C(15) bonds.

[Diversity and in vitro antitumnor activity of endophytic fungi from mangrove plants Xylocarpus].

A total of 24 biologically pure entophytic fungal strains were isolated from stems, leaves, and seed coats of Xylocarpus plants by repeated purification, and identified with Internal Transcribed Spacer (ITS) rDNA molecular method, which belonging to 14 genera, 11 families, 9 orders and 3 classes. There were differences in genus and species levels among three plant materials from different habitats and species, and it was found that the strains of Phomopsis and Colletotrichum existed in all three plant materials. In vitro assay of antitumor activity by MTT method revealed that the EtOAc extracts of 15 strains exhibited potent antitumor activity. These results suggest that it is of value for further investigation on the above fungal strains.

Aspartate metabolic flux promotes nitric oxide to eliminate both antibiotic-sensitive and -resistant Edwardsiella tarda in zebrafish.

Introduction: Metabolic reprogramming potentiates host protection against antibiotic-sensitive or -resistant bacteria. However, it remains unclear whether a single reprogramming metabolite is effective enough to combat both antibiotic-sensitive and -resistant bacteria. This knowledge is key for implementing an antibiotic-free approach. Methods: The reprogramming metabolome approach was adopted to characterize the metabolic state of zebrafish infected with tetracycline-sensitive and -resistant Edwardsiella tarda and to identify overlapping depressed metabolite in dying zebrafish as a reprogramming metabolite. Results: Aspartate was identify overlapping depressed metabolite in dying zebrafish as a reprogramming metabolite. Exogenous aspartate protects zebrafish against infection caused by tetracycline-sensitive and -resistant E. tarda. Mechanistically, exogenous aspartate promotes nitric oxide (NO) biosynthesis. NO is a well-documented factor of promoting innate immunity against bacteria, but whether it can play a role in eliminating both tetracycline-sensitive and -resistant E. tarda is unknown. Thus, in this study, aspartate was replaced with sodium nitroprusside to provide NO, which led to similar aspartate-induced protection against tetracycline-sensitive and -resistant E. tarda. Discussion: These findings support the conclusion that aspartate plays an important protective role through NO against both types of E. tarda. Importantly, we found that tetracycline-sensitive and -resistant E. tarda are sensitive to NO. Therefore, aspartate is an effective reprogramming metabolite that allows implementation of an antibiotic-free approach against bacterial pathogens.

Andhraxylocarpins†A-E: structurally intriguing limonoids from the true mangroves Xylocarpus granatum and Xylocarpus moluccensis.

Five new limonoids, including andhraxylocarpins A and B (1 and 2) which contain a 9-oxa-tricyclo[3.3.2.1(7, 10)]undecane-2-ene motif, andhraxylocarpins C and D (3 and 4), which contain a (Z)-bicyclo[5.2.1]dec-3-en-8-one substructure, and andhraxylocarpin E (5), which contains a tricyclo[3.3.1.1(3, 6)]decane-9-one scaffold, were isolated from the seeds of two true mangroves, Xylocarpus granatum and Xylocarpus moluccensis, that were collected in the estuaries of Andhra Pradesh, India. The absolute configurations of these compounds were determined by extensive NMR investigations, single-crystal X-ray diffraction analysis, and by circular dichroism and optical rotatory dispersion spectroscopy, in combination with quantum-chemical calculations. The pronounced structural diversity of limonoids from these mangroves might originate from environmental factors.

Moluccensins R-Y, limonoids from the seeds of a mangrove, Xylocarpus moluccensis.

Eight limonoids, named moluccensins R-Y (1, 2, 5-10), and six known compounds, including 6-hydroxymexicanolide (3), were isolated from the seeds of an Indian mangrove, Xylocarpus moluccensis, collected in the estuaries of Andhra Pradesh. The absolute configuration of moluccensin V (7) was confirmed by means of single-crystal X-ray diffraction analysis. The (1)H and (13)C NMR data for 6-hydroxymexicanolide (3) was assigned for the first time, and the 6R absolute configuration established by single-crystal X-ray diffraction analysis. Moluccensin R (1), 6R-hydroxymexicanolide (3), and 2-hydroxyfissinolide (4) exhibited marked antifeedant activity against the third-instar larvae of Brontispa longissima at a concentration of 1 mg/mL. The most potent compound tested was 2-hydroxyfissinolide (4), with an AFC(50) (concentration for 50% antifeedant activity) value of 94 µg/mL at 24 h.

Chemical constituents and some biological activities of plants from the genus Ceriops.

In this review, the literature data on phytochemical and biological investigations of the genus Ceriops are compiled. The Ceriops species are mangrove plants widely distributed along the sea coasts of Africa, Madagascar, South Asia, and South Pacific islands. To date, 43 diterpenes and 29 triterpenes have been reported from the embryos, fruits, hypocotyls, roots, stems, and twigs of C. tagal and C. decandra. Diterpenoids and triterpenoids are the main constituents of this genus. The isolated terpenes showed an enormous structural diversity and exhibited various biological properties, such as antitumor, antibacterial, and larvicidal activities.

Dolabranes from the Chinese Mangrove, Ceriops tagal.

Six new dolabranes, named tagalsins P-U (1-6), were isolated from stems and twigs of a Chinese mangrove, Ceriops tagal, along with seven known dolabranes, an abietane, and a pimarane. The structures of these compounds were established on the basis of spectroscopic data or comparison with data in the literature. The relative configurations of tagalsins P and Q (1, 2), two new 15,16-dinor-dolabranes, were confirmed by means of single-crystal X-ray diffraction analysis. This is the first report of 16-nordolabranes and 15,16-dinordolabranes from plants of the Ceriops genus. Tagalsins Q (2), R (3), and U (6) showed moderate antifeedant activity against the third-instar larvae of Brontispa longissima at a concentration of 1 mg/mL. However, none of the new dolabranes exhibited significant activity against human cancer cell lines.

Limonoids from the Seeds of a Hainan Mangrove, Xylocarpus granatum.

Ten new limonoids, hainangranatumins A-J (1-10), and 25 known compounds were isolated from seeds of a Chinese mangrove, Xylocarpus granatum, collected on Hainan Island. Hainangranatumins A-E (1-5) and I and J (9 and 10) are 9,10-seco-mexicanolides, whereas hainangranatumin F (6) is a limonoid possessing an 8α,30α-epoxy ring and a C1-C29 oxygen bridge. Hainangranatumin G (7) is a limonoid with a central pyridine ring, and hainangranatumin H (8) is a phragmalin 1,8,9-ortho ester. The relative configurations of hainangranatumins A and B were established by means of single-crystal X-ray diffraction analysis, and their absolute configurations were assigned on the basis of the specific rotation of the free acids obtained from alkaline hydrolysis. This is the first report of X-ray crystallographic structures of 9,10-seco-mexicanolides with a flexible C2-C30-C8 linkage. Hainangranatumins I and J (9 and 10), unusual 9,10-seco-mexicanolides with a C9-C30 linkage, are proposed to be artifacts derived from hainangranatumin C and xylomexicanin A, respectively.

Limonoids and tirucallane derivatives from the seeds of a krishna mangrove, Xylocarpus moluccensis.

Six new phragmalins, moluccensins H-M (1-6), two new andirobin-type limonoids, moluccensins N and O (7, 8), and two new tirucallane derivatives, moluccensins P and Q (9, 10), were isolated from seeds of an Indian mangrove, Xylocarpus moluccensis, together with the known compound 3beta,22S-dihydroxytirucalla-7,24-dien-23-one. The structures of these compounds were established on the basis of spectroscopic data. Moluccensins H-L were phragmalins with a C-30 carbonyl group, and moluccensin M was a unique ring-D-opened 16-norphragmalin. Moluccensins H-J possess conjugated Delta(8,9) and Delta(14,15) double bonds, moluccensins K and L contain a Delta(8,14) double bond, and moluccensin M has a characteristic C(15)-C(30) linked five-membered lactone ring. Moluccensins H and I showed moderate insecticidal activity against the fifth instar larvae of Brontispa longissima (Gestro) at a concentration of 100 mg/L.

Mexicanolides from the seeds of a Krishna mangrove, Xylocarpus moluccensis.

Two new mexicanolides, named xylomexicanolides A and B, were isolated from the seeds of an Indian mangrove, Xylocarpus moluccensis, together with four known limonoids, khayasin, angolensic acid methyl ester, khayasin T, and 2'S-methylbutanoylproceranolide. The structures of these limonoids were established on the basis of spectroscopic data. The (13)C-NMR data of khayasin were reported for the first time. Khayasin was found to exhibit marked insecticidal activity against the fifth instar larvae of Brontispa longissima (GESTRO) at a concentration of 10 mg/l.

Moluccensins A-G, phragmalins with a conjugated C-30 carbonyl group from a Krishna mangrove, Xylocarpus moluccensis.

Seven new phragmalins with a C-30 carbonyl moiety, named moluccensins A-G (1-7), among which moluccensins A-F, possessing a Delta(8,14) double bond, and moluccensin G (7), containing conjugated Delta(8,9) and Delta(14,15) double bonds, were isolated from the seeds of an Indian mangrove, Xylocarpus moluccensis. The structures of these compounds were established on the basis of single-crystal X-ray diffraction analysis and spectroscopic data. This is the first report of phragmalins with a conjugated C-30 carbonyl group.

Granatumins A-G, limonoids from the seeds of a Krishna mangrove, Xylocarpus granatum.

Seven new limonoids (1-7), named granatumins A-G, were isolated from seeds of an Indian mangrove (Xylocarpus granatum) collected from the wetlands of Krishna estuary, Andhra Pradesh. The known compounds khayasin T, tigloylseneganolide A, 6-deoxyswietenine, swietemahonolide, febrifugin A, gedunin, xylogranatinin, phaseic acid, (2R,3R)-3,4',5,7-tetrahydroxyflavanone, and (E)-4-hydroxycinnamic acid were also isolated. The structures were established on the basis of spectroscopic data. Granatumins A and B are mexicanolides with endo-conjugated Delta(8,30) and Delta(14,15) double bonds, and granatumins F and G are polyhydroxylated phragmalins found previously in plants of the Meliaceae. Khayasin T exhibited moderate insecticidal activity against fifth instar larvae of Brontispa longissima (Gestro) at a concentration of 20 mg/L.