Studies on the gametophytic development, mating behaviour and reproductive biology of Macrothelypteris torresiana (Gaudich.) Ching (Thelypteridaceae)

Macrothelypteris torresiana is a terrestrial fern belongs to the family Thelypteridaceae. It is very imperative to know the germination and growth pattern of this fern to make strategy for ex- situ conservation. In the present study germination of spore, developmental pattern of prothallium with particular emphasis on emergence of antheridia as well as archegonia, their fertilization and development of sporophytes were studied. The spores were spheroidal or reniform with broadly winged fimbriate perispore having average size of 48 ± 3.6 × 39 ± 4.2 μm. The spores started germinating just after 6 days of plating and percentage of germination was 94%. The germination pattern of spore was Vittaria type and development of gametophyte was Aspidium type. After 27 days of plating, a very distinct cordate-shaped adult gametophyte with deep apical notch and unicellular papillate hairs throughout the gametophyte was developed. The rhizoids appeared away from the apical notch of the gametophyte. The gametophyte first developed archegonia on 32^nd day, whereas antheridia were developed on 42^nd day. In isolate culture the gametophytes did not develop any sporophyte whereas in composite culture juvenile sporophytes were emerged on 77^th day. This suggests the plant has ability to reproduce only through inter-gametophytic selfing and crossing, hence decreasing the plant's capacity for colonization in a particular locality.

The antagonism between apigenin and protoapigenone to the PDK-1 target in Macrothelypteris torresiana

Apigenin and protoapigenone that both have the activities against various cancer cell lines co-exist in Macrothelypteris torresiana, while the extracts of M. torresiana couldn't achieve the fine anti-tumor effects for the existence of potent anti-tumor compounds. This study disclosed an antagonism between the two compounds on the protein level to elucidate the paradox. First, the study established the fingerprint for M. torresiana extract. The following anti-proliferation assay verified that the antagonism occurs between protoapigenone and apigenin. And then Western blot and qt-PCR were applied to evaluate the expression and transcription level of the Akt phosphorylation related targets to validate the antagonism at the protein level. Moreover, CETSA further validated the binding of PDK-1 with apigenin and protoapigenone, as well as the antagonism between the two compounds. Finally, the compound-protein complexes predicted by SYBYL-X gave the visual results for the antagonism. The results demonstrated that: Due to the structural similarity and close binding coefficients to the identical targets, when the cells were treated with apigenin and protoapigenone simultaneously, the Akt phosphorylation inhibition induced by protoapigenone would attenuate significantly. The antagonism disclosed in this paper could be a new explanation for the unsatisfied efficacy of M. torresiana extract.

The complete chloroplast genome of Macrothelypteris torresiana, a reputed medicinal fern (Thelypteridaceae)

Macrothelypteris torresiana is a reputed medicinal fern. Its complete chloroplast genome was determined by Illumina paired-end sequencing. The genome is 151,150 bp in length with 43.1% overall Guanine+Cytosine (GC) content, which is divided into four distinct parts such as a small single copy (SSC, 21,772 bp), a large single copy (LSC, 82,422 bp), and two inverted repeats (IRs, 23,478 bp each). It contains 132 genes, including 86 protein-coding genes, eight ribosomal RNA genes, 35 tRNA genes, and three pseudogenes. Maximum likelihood (ML) tree revealed that M. torresiana was closely grouped with Christella appendiculata with 100% bootstrap value.

Hepatoprotective activity of Macrothelypteris torresiana (Gaudich.) aerial parts against CCl4-induced hepatotoxicity in rodents and analysis of polyphenolic compounds by HPTLC

Macrothelypteris torresiana is a fern species belonging to family Thelypteridaceae. The present study was conducted to evaluate hepatoprotective potential of ethanol extract from M. torresiana aerial parts (EEMTAP) and detect the polyphenolic compounds present in the extract using high performance thin layer chromatography (HPTLC). Hepatoprotective potential of EEMTAP were tested at doses of 300 and 600 mg/kg, per os (p.o.), on Wistar albino rats. The extract and silymarin treated animal groups showed significant decrease in activities of different biochemical parameters like serum glutamic oxaloacetic transaminase (SGOT), serum glutamate-pyruvate transaminase (SGPT), alkaline phosphatase (ALP), which were elevated by carbon tetrachloride (CCl₄) intoxication. The levels of total bilirubin and total protein alongwith the liver weight were also restored to normalcy by EEMTAP and silymarin treatment. After CCl₄ administration the level of hepatic antioxidant enzymes such as Glutathione (GSH) and Catalase (CAT) were decreased whereas the level of hepatic lipid peroxidation (LPO) was elevated. The level of these hepatic antioxidant enzymes were also brought to normalcy by EEMTAP and silymarin treatment. Histological studies supported the biochemical findings and treatment with EEMTAP at doses 300 and 600 mg/kg, p.o. was found to be effective in restoring CCl₄-induced hepatotoxicity in rats. A simple HPTLC analysis was conducted for the detection of polyphenolic compounds in EEMTAP, and the result revealed the presence of caffeic acid as phenolic acid and quercetin as flavonoid. The proposed HPTLC method is simple, concise and provides a good resolution of caffeic acid and quercetin from other constituents present in EEMTAP.