One new spirocyclic lactone and one new benzopyran derivative from Aspergillus terreus.

One new spirocyclic lactone, terreinlactone C (1), and one new benzopyran derivative, 2,2-dimethyl-3-hydroxychroman-6-aldehyde (2), were discovered from the fungus Aspergillus terreus. The chemical structures of compounds 1 and 2 were elucidated by detailedly analyzing NMR and HRESIMS data. Compound 1 is the first natural product with a 1-oxaspiro[4.5]decan-2-one ring system and a possible biogenetic pathway is proposed. Two compounds were tested for their cytotoxic activities against five human cancer cell lines.[Formula: see text].

Cysteine Residue Containing Merocytochalasans and 17,18-seco-Aspochalasins from Aspergillus micronesiensis.

Two cysteine residue containing merocytochalasans (cyschalasins A and B, 1 and 2) and two 17,18-seco-aspochalasins (secochalasins A and B, 3 and 4) were isolated from the endophytic fungus Aspergillus micronesiensis. Cyschalasins A and B represent a new type of merocytochalasan featuring the fusion of an aspochalasin with a modified cysteine residue. Secochalasins A and B are the first 17,18-seco-aspochalasins to be reported and represent a previously undescribed carbon skeleton. Plausible biosynthetic pathways of 1-4 were proposed. Compounds 1 and 2 were cytotoxic and active against Gram-positive bacteria.

Amiaspochalasins A-H, Undescribed Aspochalasins with a C-21 Ester Carbonyl from Aspergillus micronesiensis.

Amiaspochalasins A-H (1-8), eight undescribed aspochalasins, and trichalasin D (9), a known analogue, were isolated from the solid culture of Aspergillus micronesiensis. Compounds 1-9 are aspochalasins with a C-21 ester carbonyl, and their structures were determined by spectroscopic data, X-ray crystallographic analyses, electronic circular dichroism calculations, and chemical methods. The CH3-25 in compound 1 is located at C-16 rather than C-14 in the previously reported aspochalasins, endowing 1 with an unexpected carbon skeleton. Compounds 2 and 3 are the first examples of aspochalasins with an unprecedented 5/6/6/8 tetracyclic ring system. Compounds 4 and 5 are diastereomers of aspochalasins I and J, respectively. Compounds 6 and 7 are the first aspochalasins featuring a long open-chain system, and their absolute configurations were discussed by comparing the NMR data of the hydrolysis and methyl esterification products of 4 and 5. Compound 8 is an isomeride of 9. The cytotoxic and antimicrobial effects of 1-9 were tested.

Amichalasines A-C: Three Cytochalasan Heterotrimers from Aspergillus micronesiensis PG-1.

Amichalasines A-C (1-3), which represent a new type of cytochalasan heterotrimers, were isolated from Aspergillus micronesiensis PG-1. Compounds 1 and 2 possess an undecacyclic 5/6/11/5/5/6/6/5/11/6/5 ring system, and 3 has an additional furan ring with a dodecacyclic 5/6/11/5/5/6/6/5/5/11/6/5 ring system. 1 and 2 exhibited potent cytotoxic activities through apoptosis induction mediated by caspase-3 activation and PARP degradation, and their IC50 values against HL60 cells were 1.71 and 3.74 µM, respectively.

Dibrefeldins A and B, A pair of epimers representing the first brefeldin A dimers with cytotoxic activities from Penicillium janthinellum.

Dibrefeldins A and B (1 and 2), two unexpected brefeldin A (BFA) dimers, as well as brefeldin F (3), brefeldin G (4), and 14-hydroxy-BFA (5), three new BFA derivatives, together with three new naturally occurring BFA derivatives (6-8) and four known analogues (9-12), were isolated from the fungus Penicillium janthinellum. Dibrefeldins A and B (1 and 2) represent the first examples of BFA dimers formed by an esterification between two BFA monomer units. Brefeldin F (3) has an α,ß-unsaturated γ-lactone ring, and this moiety was first discovered in naturally occurring BFA derivatives. The structures and relative/absolute configurations of these derivatives were elucidated by extensive spectroscopic methods, 13C NMR calculations, and single-crystal X-ray diffraction. Compounds 1, 2, 8, and 9 showed excellent cytotoxic activities against six cancer cell lines with IC50 values ranging from 0.01 to 4.45 µM.

Brasilane sesquiterpenoids and dihydrobenzofuran derivatives from Aspergillus terreus [CFCC 81836].

Brasilanones A-F and asperterreusines A-C, undescribed brasilane sesquiterpenoids and dihydrobenzofuran derivatives, were isolated from the marine-derived fungus Aspergillus terreus [CFCC 81836]. Their structures with absolute configurations were elucidated on the basis of spectroscopic data, X-ray crystallographic analyses, and electronic circular dichroism (ECD) calculations. Brasilanones A-F are unusual brasilane sesquiterpenoids with an α,ß-unsaturated ketone unit, interestingly, brasilanones B-D are stereo isomers. All of the isolates were evaluated for their inhibitory activities against NO production and cytotoxic activities against five human cancer cell lines (HL-60, SW-480, A-549, MCF-7, and SMMC-7721). Brasilanones A and E showed moderate inhibitory effect with NO inhibition rates of 47.7% (p < 0.001) and 37.3% (p < 0.001) at the concentration of 40 µM. Asperterreusines A showed cytotoxicity against HL-60 and SW-480 cell lines with IC50 values of 15.3 and 25.7 µM, respectively.

(±)-Terreinlactone A, a Pair of 3-Substituted δ-Lactone Enantiomers Derived from Terrein from the Fungus Aspergillus terreus.

Terreinlactone A (1a/1b), a pair of 3-substituted δ-lactone enantiomers, and terreinlactone B (2), a new biosynthetic intermediate of 1a/1b, were isolated from Aspergillus terreus, along with their biosynthetic precursor (+)-terrein (3) and (+)-isoterrein (4). Compounds 1a and 1b were separated by using a Daicel chiral-pak ASH column eluting with n-hexane-EtOH (80 : 20). The structures of 1a/1b with absolute configurations were determined by comprehensive spectroscopic analyses and electronic circular dichroic (ECD) calculations. Terreinlactone A (1) represents the first example of 1,5-seco-terrein and a biogenetic pathway is proposed from the precursor terrein via the intermediated terreinlactone B (2).

Atrichodermones A-C, three new secondary metabolites from the solid culture of an endophytic fungal strain, Trichoderma atroviride.

An endophytic fungal strain named Trichoderma atroviride was isolated from the bulb of Lycoris radiata. Following cultivation on rice medium, a novel 3-amino-5-hydroxy-5-vinyl-2-cyclopenten-1-one dimer, atrichodermone A (1), a new cyclopentenone derivative, atrichodermone B (2), and a new sesquiterpene, atrichodermone C (3), together with three known cyclopentenone derivatives (4-6) were isolated. Their structures were elucidated by extensive spectroscopic (UV, IR, ECD, HRESIMS, and NMR) data analyses, and absolute configurations of the new compounds were determined by comparing their experimental ECD spectra with structurally similar compounds and computational analyses of their electronic circular dichroism (ECD) spectra. Compounds 1-3 were evaluated for their cytotoxicity against HL60 and U937 cell lines, as well as anti-inflammatory effect against the production of the pro-inflammatory cytokines TNF-α and IL-1ß.

6,8-Di-C-methyl-flavonoids with neuroprotective activities from Rhododendron fortunei.

Six 6,8-di-C-methyl-flavonoids, (2R,3R)-6,8-di-C-methyl-5,7,4'-trihydroxyflavanonol 7-O-ß-d-gluco-pyranoside (1), (2R,3R)-6,8-di-C-methyl-5,7,4'-trihydroxyflavanonol 7-O-ß-d-xylopyranosyl(1→6)-ß-d-glucopyranoside (2), 6,8-di-C-methylkaempferol 7-O-ß-d-glucopyranoside (3), (2R)-farrerol (4a), (2R/2S)-farrerol 7-O-ß-d-glucopyranoside (5), and (2R/2S)-farrerol 7-O-ß-d-xylopyranosyl(1→6)-ß-d-glucopyranoside (6), and four known analogues, farrerol (4b), (2R,3R)-6,8-di-C-methyldihydrokae-mpferol (7), 6,8-di-C-methylkaempferol 7-O-ß-d-glucopyranoside (8), and 6,8-di-C-methylkaempferol (9), were isolated from the twigs and leaves of Rhododendron fortunei. The structures of compounds 1-9 were determined by spectroscopic analyses (HRESIMS, 1D and 2D NMR, and CD) and chemical methods. Compounds 1-9 were evaluated for their neuroprotective effects on the human neuroblastoma SH-SY5Y cells apoptosis induced by hydrogen peroxide (H2O2) and amyloid ß peptide (Aß), respectively. Compounds 1-3 and 5-9 exhibited significant neuroprotective effects against H2O2-induced SH-SY5Y cell apoptosis, and compound 8 exhibited the strongest activity with a improvement of cell viability by about 30% at the concentration of 10µM. Compounds 1-9 showed significant neuroprotective effects against Aß-induced SH-SY5Y cell apoptosis.

Neolignans with a Rare 2-Oxaspiro[4.5]deca-6,9-dien-8-one Motif from the Stem Bark of Cinnamomum subavenium.

Two pairs of racemic spirodienone neolignans with a rare 2-oxaspiro[4.5]deca-6,9-dien-8-one motif, named (±)-subaveniumins A (1) and B (2), were isolated from the bark of Cinnamomum subavenium. The chiral separation of the (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers was accomplished via high-performance liquid chromatography on a chiral column. Their structures were elucidated using single-crystal X-ray diffraction and spectroscopic analyses (UV, IR, HRESIMS, and 1D and 2D NMR). The absolute configurations of the enantiomers were determined by comparing the experimental and calculated electronic circular dichroic spectra. The (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers exhibited moderate inhibitory effects against NO production in RAW264.7 mouse macrophages induced by lipopolysaccharide, with IC50 values of 17.9, 5.6, 15.1, and 4.3 µM, respectively.

A rare case of watery diarrhea, hypokalemia and achlorhydria syndrome caused by pheochromocytoma.

BACKGROUND: A rare syndrome of watery diarrhea, hypokalemia and achlorhydria (WDHA) is usually caused by pancreatic endocrine tumors that secrete excessive vasoactive intestinal polypeptide (VIP). Here we report a rare case of WDHA caused by a pheochromocytoma. CASE PRESENTATION: A 45-year old male presented with persistent and progressive watery diarrhea for half a year, and was treated with dialysis due to azotemia, hypokalemia, hypercalcemia and metabolic acidosis. A right adrenal mass was found by ultrasonography, and Positron Emission Tomography-Computed Tomography (PET-CT) showed the tumor was hyper-metabolic. Levels of plasma normetanephrine (NMN) and serum chromogranin A (CgA) were significantly elevated. Immunohistochemistry analysis of the adrenal tumor was strongly positive for CgA, synaptophysin and VIP. The patient fully recovered from WDHA syndrome soon after surgery, as reflected in that diarrhea stopped, levels of plasma NMN, serum CgA, and electrolytes returned to normal thus no dialysis was needed. The patient remained disease free in a 12-months follow-up period. CONCLUSION: We report an extremely rare case of pheochromocytoma causing WDHA syndrome and uremia, which the patient completely recovered from after tumor resection.

[Expression of NMBR in myometrium in pregnant mice at different gestational ages and its relation with parturition].

OBJECTIVE: To investigate the spatiotemporal expression of neuromedin B receptor (NMBR) in mice myometrium at different pregnant stages, as well as its mechanism and relation with parturition. METHODS: The pregnant mice were divided into no-pregnancy (NP), early pregnancy (EP), mid-pregnancy (MP), late-pregnancy (LP), parturition (PT) and postpartum (PP) groups (12 mice in each group), according to pregnant stage. The mRNA and protein expression of NMBR, HSP70 and IL-6 were detected in myometrium in pregnant mice by semi-quantitative RT-PCR and Western blot, while NF-kappaB-P65 DNA binding activity was determined by NoShift transcription factor assay kits, respectively. Their relation with parturition was analyzed. RESULTS: The mRNA expression level of NMBR in the PT group was significantly higher than that in the NP, EP, LP and PP groups (P<0.05), but this difference was not observed in the MP group (P>0.05). The NMBR protein in PT group was significantly higher than that in the other 5 groups (P<0.01). NF-kappaB-P65 DNA binding activity at PT group was remarkably higher than that in the NP, LP and PP groups (P<0.05). The expression of IL-6 mRNA was significantly higher than that in the NP, LP and PP groups (P<0.05), its protein expression in PT and LP groups was significantly higher than that in the NP and PP groups (P<0.05). The expression of HSP70 mRNA in the PT group was significantly higher than that in the NP and PP groups (P<0.05), and the protein of HSP70 was significantly up-regulated in PT and PP groups compared with in NP and LP groups (P<0.05). The DNA-binding activity of P65 was positively correlated to the mRNA expression of NMBR and IL-6 (r=0.40, P<0.01; r=0.30, P<0.05), so were positively correlated to DNA-binding activity of P65, mRNA expression of HSP70 and NMBR ( r=0.40, P<0.01; r=0.49, P<0.01). DNA-binding activity of P65 did not correlate with the mRNA expression of HSP70. CONCLUSION: The mRNA and protein expressions of NMBR reach a peak at the onset of labor. NMBR may play an important role in the parturition via NF-kappaB P65-IL-6 signal transduction pathway. It may also influence the onset of labor by regulating HSP70, but this role does not rely on P65 pathway.

Molecular cloning of a novel mouse testis-specific spermatogenic cell apoptosis inhibitor gene mTSARG7 as a candidate oncogene.

A novel mouse gene, mTSARG7 (GenBank accession No. AY489184), with a full cDNA length of 2279 bp and containing 12 exons and 11 introns, was cloned from a mouse expressed sequence tag (GenBank accession No. BE644543) that was significantly up-regulated in cryptorchidism. The gene was located in mouse chromosome 8A1.3 and encoded a protein containing 403 amino acid residues that was a new member of the acyltransferase family because the sequence contained the highly conserved phosphate acyltransferase (PlsC) domain existing in all acyltransferase-like proteins. The mTSARG7 protein and AU041707 protein shared 83.9% identity in 402 amino acid residues. Expression of the mTSARG7 gene was restricted to the mouse testis. The results of the in situ hybridization analysis revealed that the mTSARG7 mRNA was expressed in mouse spermatogonia and spermatocytes. Subcellular localization studies showed that the EGFP-tagged mTSARG7 protein was localized in the cytoplasm of GC-1 spg cells. The mTSARG7 mRNA expression was initiated in the mouse testis in the second week after birth, and the expression level increased steadily with spermatogenesis and sexual maturation of the mouse. The results of the heat stress experiment showed that the mTSARG7 mRNA expression gradually decreased as the heating duration increased. The pcDNA3.1 Hygro(-)/mTSARG7 plasmid was constructed and introduced into GC-1 spg cells by liposome transfection. The mTSARG7 can accelerate GC-1 spg cells, causing them to traverse the S-phase and enter the G2-phase, compared with the control group where this did not occur as there was no transfection of mTSARG7. In conclusion, our results suggest that this gene may play an important role in spermatogenesis and the development of cryptorchid testes, and is a testis-specific apoptosis candidate oncogene.