First Report of Brown Leaf Rot Disease on Dendrobium nobile Caused by Xylaria flabelliformis in Guizhou Province, China.

Dendrobium nobile is the largest species of the Orchidaceae family and produces dendrobine, a compound with medicinal properties (Sarsaiya et al., 2020a; Sarsaiya et al., 2024; Qian et al., 2024). The accumulation of dendrobine in D. nobile is regulated by various pathogenic fungi, which directly and indirectly influence dendrobine biosynthesis (Sarsaiya et al., 2019a; Sarsaiya et al., 2019b). In a field planted with D. nobile in Guizhou Province, China, small lesions were initially observed on the upper part of the leaves from May to June 2019, which later developed into larger brown necrotic leaf lesions. Over time, these lesions greatly impacted the medicinal value (dendrobine) and productivity of the plant. A pure culture of Xylaria flabelliformis from infected wild D. nobile leaves was recovered and subsequently cultured on potato dextrose agar (PDA) at 25 °C for 5 days. Xylaria flabelliformis grew slowly and was composed of white mycelia. Colonies were initially white, with a regular margin, and formed stromata that consisted of mycelia sterilia without ascospores. We identified the strain as Xylaria flabelliformis based on its morphological characteristics (Liu et al., 2007) and by sequencing elongation factor-1α (EF-1α). The length of the DNA sequence of EF-1α that was used for the analysis of Xylaria flabelliformis was 1188 bp. BLASTx (nucleotide 6-frame translation-protein) analysis using the National Center for Biotechnology Information database showed that the obtained protein sequence (BLASTx protein accession no.: UTS95822.1, BLASTn nucleotide sequence accession no.: MW508334.1) had the highest similarity (98.21%) with the X. flabelliformis hypothetical protein (TRX95197.1) based on a thorough phylogenetic comparison with other Xylaria species. Healthy D. nobile seedlings were planted in pots and sterilized. The terminal leaves were excised from all pre-sterilised D. nobile seedlings and inoculated with Xylaria flabelliformis mycelial plugs, whereas sterile PDA plugs and moist cotton plugs were used as controls. All seedlings were maintained under optimum temperature and humidity conditions (25 °C and 80%, respectively) for seven days for observation and analysis. All experiments were performed in triplicate. After the incubation period, brown leaf rot lesions were observed for the first time on the inoculated D. nobile leaves, but no symptoms were observed on the leaves of the two control groups (sterile PDA plugs and moist cotton plugs). To complete Koch's postulates, Xylaria flabelliformis was re-isolated and identified from all diseased tissues by DNA sequencing of the EF-1α. It was determined for the first time that Xylaria flabelliformis can cause brown leaf lesions in D. nobile. Moreover, the pathogenicity of Xylaria flabelliformis in D. nobile has not been previously reported (Mead et al., 2019; Meng et al., 2019; Sarsaiya et al., 2019a; Sarsaiya et al., 2020b; Chen et al., 2023; Rinchen, 2023; Cao et al., 2024). To the best of our knowledge, this is the first report of BLRS lesions in D. nobile leaves caused by Xylaria flabelliformis in Guizhou Province, China. Identification of Xylaria flabelliformis as a pathogen of D. nobile is crucial for advancing effective management and control practices against brown leaf rot disease. This discovery provides valuable insights into the development of targeted strategies to mitigate the impact of Xylaria flabelliformis on D. nobile, safeguard medicinal properties such as dendrobine, and enhance overall productivity.

First Report of Blight Caused by Rhizoctonia solani AG4-HGI on Pinellia ternata in Guizhou, China.

Pinellia ternata (Thumb.) has been used for over 1000 years as a traditional Chinese herbal medicine (Ying et al. 2007) and is widely cultivated in Guizhou Province, China. It is cultivated over an area of 2000 hectares, and is of great value to underdeveloped regions. In April 2020, blight was observed in a field of P. ternatain Bijie County, Guizhou Province, China (27°30'N, 105°28'E). Around 20 hectares of P. ternata were surveyed and the disease incidence ranged from 10 to 12%. The disease symptoms included light brown lesions formed on the stems near the soil line. The color of the lesions became darker, and the stems became constricted around the lesions and broke, associated with the leaf blight. To identify the causal agent of this blight, 22 diseased plants (about 30 d-old） were collected, the margins of the infected parts were cut into small pieces (5 mm) and surface disinfested with 1% NaOCl for 10 min, 75% ethanol for 30 s, and rinsed three times in sterile distilled water. The pieces were blotted dry with sterile filter paper and placed on potato dextrose agar (PDA, Hopebio, China), incubated at 28℃ in darkness until fungal hyphae growth was visible. Sixteen cultures with different morphologies were recovered from the samples. When representative isolates of each culture type were inoculated onto plants, one produced similar blight symptoms. The representative isolate was called CD-1. The colony color was first white but turned light brown after grown on PDA for 6-7 d, and produced dark brown sclerotia. The hyphae were branched at right angles, with a slight constriction at the base of the branches and a septum near the junction where the branch separates from the main hyphae. Hyphal cells were stained with 0.5% Safranin O and 3% KOH and were observed to be multinucleate. These morphological features indicated that CD-1 likely is R. solani (Sneh et al. 1991). When paired with tester strains AG1 and AG4(provided by Dr. Genhua Yang, Yunnan Agricultural University). CD-1 showed anastomosis with isolate of AG4 (Fenille et al. 2002). Genomic DNA was extracted from the isolate (Thangaraj et al. 2018) using a fungal genomic DNA extraction kit (Tiangen, China). The internal transcribed spacer (ITS) regions were amplified using the primers ITS1/ITS4 (White et al. 1990). A 535 bp fragment was amplified that showed 99% coverage and 99.4% identity with an isolate of R. solani AG4-HGI (GenBank: HG934417). The gene sequence was deposited in GenBank as accession #OL518945. Pathogenicity tests were performed using 30 d-old plants planted in sterilized soil in pots. Cut mycelial discs (diameter 6 mm) from 3-day-old PDA cultures and placed beside stems of 21 healthy plants. Nine plants treated with agar plugs were control samples. Inoculated plants were maintained at 24 ± 5℃ in a green house and watered every two days with sterilized water. Typical blight symptoms developed on the inoculated plants at d 3-5 post inoculation, whereas the control plants remained healthy. The experiments were repeated three times, and the isolates was re-isolated from the inoculated plants and identified as R. solaniAG4 by morphological features and molecular method. R. solani has been reported to cause blight of many plants such as coffee (Ren et al. 2018) and sesame (Cochran et al. 2018). To the best of our knowledge, this is the first report of R. solani AG4-HGI causing disease on P. ternate, both in China and worldwide. This finding suggests that this pathogen may cause a threat to cultivation and production of P. terenata.

Molecular Identification of Endophytic Fungi and Their Pathogenicity Evaluation Against Dendrobium nobile and Dendrobium officinale.

: Dendrobium are tropical orchid plants that host diverse endophytic fungi. The role of these fungi is not currently well understood in Dendrobium plants. We morphologically and molecularly identified these fungal endophytes, and created an efficient system for evaluating the pathogenicity and symptoms of endophytic fungi on Dendrobium nobile and Dendrobium officinale though in vitro co-culturing. ReThe colony morphological traits of Dendrobium myco-endophytes (DMEs) were recorded for their identification. Molecular identification revealed the presence of Colletotrichum tropicicola, Fusarium keratoplasticum, Fusarium oxysporum, Fusarium solani, and Trichoderma longibrachiatum. The pathogenicity results revealed that T. longibrachiatum produced the least pathogenic effects against D. nobile protocorms. In seedlings, T. longibrachiatum showed the least pathogenic effects against D. officinale seedlings after seven days. C. tropicicola produced highly pathogenic effects against both Dendrobium seedlings. The results of histological examination of infected tissues revealed that F. keratoplasticum and T. longibrachiatum fulfill Koch's postulates for the existence of endophytes inside the living tissues. The DMEs are cross-transmitted inside the host plant cells, playing an important role in plant host development, resistance, and alkaloids stimulation.

Analysis of the structure and activity of the promoter regions of the metallothionein genes of the freshwater pearl mussel Hyriopsis schlegelii.

To investigate the regulation of metallothionein genes (HsMTs) of Hyriopsis schlegelii, 1,121-bp and 1,270-bp regions of the HsMT1 and HsMT2 promoters were cloned and analyzed, respectively. The two promoters shared partially conserved features and possessed distinct characteristics such as the number or position of metal response elements (MREs). Further analysis of the HsMT1 and HsMT2 promoters was performed by the reporter assay using the luciferase gene. Both promoters were activated by various metals, and presented different levels of metal ions inducibility in human hepatoblastoma cells. Deletion mutant assays demonstrated that both the longest promoter regions achieved the maximum inducibility, and the metal inducibility was dependent on the presence of the MRE in HsMT1 and the distal MRE in HsMT2. In addition, we cloned a putative metal responsive transcription factor (hereby designated as HsMTF-like) and studied its effect on HsMTs expression in human hepatoblastoma cells. An in vivo assay demonstrated that HsMTF-like activates basal HsMTs transcription level, and the MRE in the HsMTs promoter mediates this activation process. Moreover, this basal transcription level can be further boosted by zinc treatment. In conclusion, the regulation mechanism for MT activation in H. schlegelii should be evolutionarily conserved.

Enhancing dendrobine production in Dendrobium nobile through mono-culturing of endophytic fungi, Trichoderma longibrachiatum (MD33) in a temporary immersion bioreactor system.

Introduction: Dendrobine, a valuable alkaloid found in Dendrobium nobile, possesses significant pharmaceutical potential. Methods: In this study, we explored innovative approaches to enhance dendrobine production by utilizing endophytic fungi in a Temporary Immersion Bioreactor System (TIBS, Nanjing BioFunction Co. Ltd., China) and traditional test bottles. Dendrobine was unequivocally identified and characterised in D. nobile co-culture seedlings through UHPLC analysis and LC-MS qTOF analysis, supported by reference standards. Results: The CGTB (control group) and EGTB (experimental group) 12-month-old D. nobile seedlings exhibited similar peak retention times at 7.6±0.1 minutes, with dendrobine identified as C16H25NO2 (molecular weight 264.195). The EGTB, co-cultured with Trichoderma longibrachiatum (MD33), displayed a 2.6-fold dendrobine increase (1804.23 ng/ml) compared to the CGTB (685.95 ng/ml). Furthermore, a bioanalytical approach was applied to investigate the mono-culture of T. longibrachiatum MD33 with or without D. nobile seedlings in test bottles. The newly developed UHPLC-MS method allowed for dendrobine identification at a retention time of 7.6±0.1 minutes for control and 7.6±0.1 minutes for co-culture. Additionally, we explored TIBS to enhance dendrobine production. Co-culturing D. nobile seedlings with Trichoderma longibrachiatum (MD33) in the TIBS system led to a substantial 9.7-fold dendrobine increase (4415.77 ng/ml) compared to the control (454.01 ng/ml) after just 7 days. The comparative analysis of dendrobine concentration between EGTB and EGTIBS highlighted the remarkable potential of TIBS for optimizing dendrobine production. Future research may focus on scaling up the TIBS approach for commercial dendrobine production and investigating the underlying mechanisms for enhanced dendrobine biosynthesis in D. nobile. The structural elucidation of dendrobine was achieved through 1H and 13C NMR spectroscopy, revealing a complex array of proton environments and distinct carbon environments, providing essential insights for the comprehensive characterization of the compound. Discussion: These findings hold promise for pharmaceutical and industrial applications of dendrobine and underline the role of endophytic fungi in enhancing secondary metabolite production in medicinal plants.

Bulbil initiation: a comprehensive review on resources, development, and utilisation, with emphasis on molecular mechanisms, advanced technologies, and future prospects.

Bulbil is an important asexual reproductive structure of bulbil plants. It mainly grows in leaf axils, leaf forks, tubers and the upper and near ground ends of flower stems of plants. They play a significant role in the reproduction of numerous herbaceous plant species by serving as agents of plant propagation, energy reserves, and survival mechanisms in adverse environmental conditions. Despite extensive research on bulbil-plants regarding their resources, development mechanisms, and utilisation, a comprehensive review of bulbil is lacking, hindering progress in exploiting bulbil resources. This paper provides a systematic overview of bulbil research, including bulbil-plant resources, identification of development stages and maturity of bulbils, cellular and molecular mechanisms of bulbil development, factors influencing bulbil development, gene research related to bulbil development, multi-bulbil phenomenon and its significance, medicinal value of bulbils, breeding value of bulbils, and the application of plant tissue culture technology in bulbil production. The application value of the Temporary Immersion Bioreactor System (TIBS) and Terahertz (THz) in bulbil breeding is also discussed, offering a comprehensive blueprint for further bulbil resource development. Additionally, additive, seven areas that require attention are proposed: (1) Utilization of modern network technologies, such as plant recognition apps or websites, to collect and identify bulbous plant resources efficiently and extensively; (2) Further research on cell and tissue structures that influence bulb cell development; (3) Investigation of the network regulatory relationship between genes, proteins, metabolites, and epigenetics in bulbil development; (4) Exploration of the potential utilization value of multiple sprouts, including medicinal, ecological, and horticultural applications; (5) Innovation and optimization of the plant tissue culture system for bulbils; (6) Comprehensive application research of TIBS for large-scale expansion of bulbil production; (7) To find out the common share genetics between bulbils and flowers.

Neurotropic virus infection and neurodegenerative diseases: Potential roles of autophagy pathway.

Neurodegenerative diseases (NDs) constitute a group of disorders characterized by the progressive deterioration of nervous system functionality. Currently, the precise etiological factors responsible for NDs remain incompletely elucidated, although it is probable that a combination of aging, genetic predisposition, and environmental stressors participate in this process. Accumulating evidence indicates that viral infections, especially neurotropic viruses, can contribute to the onset and progression of NDs. In this review, emerging evidence supporting the association between viral infection and NDs is summarized, and how the autophagy pathway mediated by viral infection can cause pathological aggregation of cellular proteins associated with various NDs is discussed. Furthermore, autophagy-related genes (ARGs) involved in Herpes simplex virus (HSV-1) infection and NDs are analyzed, and whether these genes could link HSV-1 infection to NDs is discussed. Elucidating the mechanisms underlying NDs is critical for developing targeted therapeutic approaches that prevent the onset and slow the progression of NDs.

Analysis of the response mechanisms of Pinellia ternata to terahertz wave stresses using transcriptome and metabolic data.

Pinellia ternata (Thunb.) Breit. (Araceae), a significant medicinal plant, has been used to treat various diseases for centuries. Terahertz radiation (THZ) is located between microwaves and infrared rays on the electromagnetic spectrum. THZ possesses low single-photon energy and a spectral fingerprint, but its effects on plant growth have not yet been investigated. The study's primary objective was to examine the transcriptome and metabolome databases of the SY line to provide a new perspective for identifying genes associated with resistance and growth promotion and comprehending the underlying molecular mechanism. Variations in the biological characteristics of P. ternata grown under control and experimental conditions were analyzed to determine the effect of THZ. Compared with the control group, phenotypic variables such as leaf length, petiole length, number of leaves, leaf petiole diameter, and proliferation coefficient exhibited significant differences. P. ternata response to THZ was analyzed regarding the effects of various coercions on root exudation. The experimental group contained considerably more sugar alcohol than the control group. The transcriptome analysis revealed 1,695 differentially expressed genes (DEGs), including 509 upregulated and 1,186 downregulated genes. In the KEGG-enriched plant hormone signaling pathway, there were 19 differentially expressed genes, 13 of which were downregulated and six of which were upregulated. In the metabolomic analysis, approximately 416 metabolites were uncovered. There were 112 DEMs that were downregulated, whereas 148 were upregulated. The P. ternata leaves displayed significant differences in phytohormone metabolites, specifically in brassinolide (BR) and abscisic acid (ABA). The rise in BR triggers alterations in internal plant hormones, resulting in faster growth and development of P. ternata. Our findings demonstrated a link between THZ and several metabolic pathway processes, which will enhance our understanding of P. ternata mechanisms.

Natural foods resources and dietary ingredients for the amelioration of Helicobacter pylori infection.

Helicobacter pylori (H. pylori) is a gastric-persistent pathogen that can cause peptic ulcer disease, gastric cancer, and mucosal-associated lymphoid tissue lymphoma. This pathogen is commonly treated with antibiotic-based triple or quadruple therapy. However, antibiotic therapy could result in the bacterial resistance, imbalance of gut microbiota, and damage to the liver and kidneys, etc. Therefore, there is an urgent need for alternative therapeutic strategies. Interestingly, natural food resources, like vegetables, fruits, spices, and edible herbs, have potent inhibitory effects on H. pylori. In this review, we systematically summarized these foods with supporting evidence from both animal and clinical studies. The results have indicated that natural foods may possess temporary inhibition effect on H. pylori rather than durable eradication, and may help to reduce H. pylori colonization, enhance the effect of antibiotics and modulate the host's immune response.

Transcriptome Analysis of Dendrobine Biosynthesis in Trichoderma longibrachiatum MD33.

Dendrobine is a representative component of Dendrobium nobile, and its pharmacological effects have been extensively studied. Trichoderma longibrachiatum MD33 was isolated from the stem of Dendrobium nobile which can produce dendrobine. In order to understand the effect of Methyl Jasmonate (MeJA) on the production of dendrobine, transcriptome analysis was performed after MeJA treatment in the MD33 and control groups. The dendrobine production of MeJA (20 µmol/L) treatment group was 44.6% higher than that of control. In this study, the RNA sequencing technology was applied, a total of 444 differentially expressed genes (DEGs) in the control and MeJA treatment groups, including 226 up-regulated genes and 218 down-regulated genes. The Kyoto Encyclopedia of Genes and Genomes annotation showed that numbers of DEGs were associated with the putative alkaloid biosynthetic pathway in T Trichoderma longibrachiatum MD33. Several MVA pathway enzyme-coding genes (isopentenyl-diphosphate Delta-isomerase, iphosphomevalonate decarboxylase and farnesyl diphosphate synthase) were found to be differentially expressed, suggesting an active precursor supply for alkaloid biosynthesis after MeJA treatment, in other wise, dendrobine may synthesis through the MVA pathway in MD33. Numerous MeJA-induced P450 family genes, aminotransferase genes and methyltransferase genes were identified, providing several important candidates to further elucidate the dendrobine biosynthetic pathway of T. longibrachiatum MD33. Furthermore, several MeJA-induced transcription factors (TFs) encoding genes were identified, suggesting a complex genetic network affecting the dendrobine in T. longibrachiatum MD33. These findings reveal the regulation mechanism underlying the MeJA-induced accumulation of dendrobine in T. longibrachiatum MD33.

Transcriptomic analysis of Pinellia ternata (Thunb.) Breit T2 plus line provides insights in host responses resist Pectobacterium carotovorum infection.

Transcriptome is used to determine the induction response of Pinellia ternata (Thunb.) Breit T2 plus line (abbreviated as PT2P line) infected with Pectobacterium carotovorum. The main objective of the study was to deal with the transcriptome database of PT2P line resistance to soft rot pathogens to provide a new perspective for identifying the resistance-related genes and understanding the molecular mechanism. Results indicated that water soaking and tissue collapse started at 20 h after PT2P line was infected by P. carotovorum. A total of 1360 and 5768 differentially expressed genes (DEGs) were identified at 0 h and 20 h, respectively. After 20 h of infection, growth and development-related pathways were inhibited. Meanwhile, DEGs were promoted the colonization of P. carotovorum pathogens in specific cell wall modification processes at the early infected stage. A shift to a defensive response was triggered at 0 h. A large number of DEGs were mainly up-controlled at 20 h and were substantially used in the pathogen recognition and the introduction of signal transformation cascades, secondary metabolites biosynthesis, pathogenic proteins activation, transcription aspects and numerous transporters. Furthermore, our data provided novel insights into the transcript reprogramming of PT2P line in response to P. carotovorum infestation.

New Insights into Detection of a Dendrobine Compound From a Novel Endophytic Trichoderma longibrachiatum Strain and Its Toxicity Against Phytopathogenic Bacteria.

Dendrobium nobile is the only plant that could produce the natural bioactive dendrobine. No other source of dendrobine has been found to date except from D. nobile and via chemical synthesis. In this study, we aimed to examine the potential fungal endophyte isolated from D. nobile stem segments using the molecular method and to detect dendrobine compound through high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography with tandem mass spectrometry (LC-MS/MS) and their metabolite for their antibacterial activity. The potential dendrobine producer strain was recognized as Trichoderma longibrachiatum based on molecular DNA sequencing and GenBank databases. The T. longibrachiatum MD33 produced dendrobine and other compounds in a potato dextrose medium (PDM), as confirmed by HPLC retention time peak analysis. The HPLC results revealed that T. longibrachiatum MD33 biomass showed a peak retention time of 5.28 ± 0.2 min, similar to wild D. nobile stem dendrobine (5.32 ± 0.2 min) and standard chemical reference dendrobine (5.30 ± 0.2 min), indicating the presence of dendrobine in the fungal biomass. Results of GC-MS and LC-MS analysis revealed that T. longibrachiatum MD33 produced the same molecular weight (263 in GC-MS and 264.195 in LC-MS) of dendrobine as compared with standard chemical reference dendrobine and D. nobile dendrobine. Antibacterial activity data revealed that T. longibrachiatum MD33 produced the strongest bactericidal activity against Bacillus subtilis, Bacillus mycoides, and Staphylococcus species, and the diameter of the bacterial growth inhibition zone was 12 ± 0.2, 9 ± 0.2, and 8 ± 0.2 mm, respectively. To the best of our knowledge, this was the first study to investigate T. longibrachiatum as a dendrobine producer, and the results revealed that T. longibrachiatum was directly involved in the potential production of a similar bioactive compound to D. nobile (dendrobine). In addition, the T. longibrachiatum metabolite exhibited potent antibacterial activity and can be a potential strain for medical and industrial purposes.

The anti-diabetic activities, gut microbiota composition, the anti-inflammatory effects of Scutellaria-coptis herb couple against insulin resistance-model of diabetes involving the toll-like receptor 4 signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria-coptis herb couple (SC) is one of the well-known herb couples in many traditional Chinese compound formulas used for the treatment of diabetes mellitus (DM), which has been used to treat DM for thousands of years in China. AIM OF THE STUDY: Few studies have confirmed in detail the anti-diabetic activities of SC in vivo and in vitro. The present investigations aimed to evaluate the anti-diabetic activity of SC in type 2 diabetic KK-Ay mice and in RAW264.7 macrophages to understand its possible mechanism. MATERIALS AND METHODS: High-performance liquid chromatography with ultraviolet detection (HPLC-UV) and LC-LTQ-Orbitrap Pro mass spectrometry were used to analyze the active ingredients of SC extracts and control the quality. A type 2 diabetic KK-Ay mice model was established by high-fat diet. Body weight, fasting blood glucose levels, fasting blood insulin levels, glycosylated hemoglobin and glycosylated serum protein were measured. The effects of SC on total cholesterol (TC), high-density lipoprotein (HDL) and triglyceride (TG) levels were examined. The lipopolysaccharide (LPS), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) levels were measured. Gut microbial communities were assayed by polymerase chain reaction (PCR) and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) methods. The expressions of Toll-like receptor 4 (TLR4) and MyD88 protein in the colons were measured by western blot. In RAW264.7 macrophages, IL-6, TNF-α, TLR4 and MyD88 protein levels were measured by enzyme-linked immunosorbent assay (ELISA) kits or western blot, and the mRNA expression of IL-6, TNF-α and TLR4 was examined by the real time PCR. RESULTS: The present results showed that the SC significantly increased blood HDL and significantly reduced fasting blood glucose, fasting blood insulin, glycosylated hemoglobin, glycosylated serum protein, TC, TG, LPS, IL-6 and TNF-α levels (P < 0.05 or P < 0.01) in type-2 diabetic KK-Ay mice. Furthermore, SC could regulate the structure of intestinal flora. Additionally, the expressions of TLR4 and MyD88 protein in the colons were significantly decreased in the model group (P < 0.05 or P < 0.01). However, SC had no significant effect on weight gain. In RAW264.7 macrophages, SC containing serum (SC-CS) (5%, 10% and 20%) significantly decreased IL-6, TNF-α, TLR4 and MyD88 protein levels and the mRNA expression of IL-6, TNF-α and TLR4 (P < 0.05 or P < 0.01). CONCLUSIONS: The anti-diabetic effects of SC were attributed to its regulation of intestinal flora and anti-inflammation involving the TLR4 signaling pathway. These findings provide a new insight into the anti-diabetic application for SC in clinical settings and display the potential of SC in the treatment of DM.