Overexpression of AtMYB2 Promotes Tolerance to Salt Stress and Accumulations of Tanshinones and Phenolic Acid in Salvia miltiorrhiza.

Salvia miltiorrhiza is a prized traditional Chinese medicinal plant species. Its red storage roots are primarily used for the treatment of cardiovascular and cerebrovascular diseases. In this study, a transcription factor gene AtMYB2 was cloned and introduced into Salvia miltiorrhiza for ectopic expression. Overexpression of AtMYB2 enhanced salt stress resistance in S. miltiorrhiza, leading to a more resilient phenotype in transgenic plants exposed to high-salinity conditions. Physiological experiments have revealed that overexpression of AtMYB2 can decrease the accumulation of reactive oxygen species (ROS) during salt stress, boost the activity of antioxidant enzymes, and mitigate oxidative damage to cell membranes. In addition, overexpression of AtMYB2 promotes the synthesis of tanshinones and phenolic acids by upregulating the expression of biosynthetic pathway genes, resulting in increased levels of these secondary metabolites. In summary, our findings demonstrate that AtMYB2 not only enhances plant tolerance to salt stress, but also increases the accumulation of secondary metabolites in S. miltiorrhiza. Our study lays a solid foundation for uncovering the molecular mechanisms governed by AtMYB2 and holds significant implications for the molecular breeding of high-quality S. miltiorrhiza varieties.

Molten salts for efficient removal of radioactive contaminants from stainless steel surface: Mechanisms and applications.

Here, we have demonstrated an innovative decontamination strategy using molten salts as a solvent to clean stubborn uranium contaminants on stainless steel surfaces. The aim of this work was to investigate the evolutionary path of contaminants in molten salts to reveal the decontamination mechanism, thus providing a basis for the practical application of the method. Thermodynamic analysis revealed that alkali metal hydroxides, carbonates, chlorides and nitrates can react with uranium oxides (UO3 and U3O8) to form various uranates. Notably, the decontamination mechanism was elucidated by analyzing the chemical composition of the contaminants in the molten salts and the surface morphology of the specimens considering NaOH-Na2CO3-NaCl melt as the decontaminant. The decontamination process involved two stages: a rapid decontamination stage dominated by the thermal effect of molten salt, and a stable decontamination stage governed by the chemical reactions and diffusion of molten salt. Subsequently, a multiple decontamination strategy was implemented to achieve high decontamination rates and low residual radioactivity. Within the actual cleaning time of 30 min, the decontamination efficiency (DE) of UO3-contaminated specimens reached 97.8% and 93.0% for U3O8-contaminated specimens. Simultaneously, the radioactivity levels of all specimens were reduced to below the control level for reuse in the nuclear domain. Particularly, the actual radioactive waste from the nuclear industry reached a reusable level of radioactivity after decontamination. The NaOH-Na2CO3-NaCl melt outperforms conventional chemical solvents and may be one of the most rapid and efficient decontaminants for stubborn uranium contamination of metal surfaces, which provides insights in regard to handling nuclear waste.

A common thalamic hub for general and defensive arousal control.

The expression of defensive responses to alerting sensory cues requires both general arousal and a specific arousal state associated with defensive emotions. However, it remains unclear whether these two forms of arousal can be regulated by common brain regions. We discovered that the medial sector of the auditory thalamus (ATm) in mice is a thalamic hub controlling both general and defensive arousal. The spontaneous activity of VGluT2-expressing ATm (ATmVGluT2+) neurons was correlated with and causally contributed to wakefulness. In sleeping mice, sustained ATmVGluT2+ population responses were predictive of sensory-induced arousal, the likelihood of which was markedly decreased by inhibiting ATmVGluT2+ neurons or multiple downstream pathways. In awake mice, ATmVGluT2+ activation led to heightened arousal accompanied by excessive anxiety and avoidance behavior. Notably, blocking their neurotransmission abolished alerting stimuli-induced defensive behaviors. These findings may shed light on the comorbidity of sleep disturbances and abnormal sensory sensitivity in specific brain disorders.

Decontamination of uranium-containing radioactive waste from stainless steel surfaces using NaOH-based molten salts.

Herein, we report a new strategy for the rapid removal of uranium-containing contaminants from metal surfaces, and it relies on decontaminants made of NaOH-based molten salts. The addition of Na2CO3 and NaCl to NaOH exhibited superior decontamination performance, with a decontamination rate of 93.8% within 12 min, outdoing the performance of the single NaOH molten salt. The experimental results demonstrated that the synergistic effects between CO32- and Cl- promoted the corrosion efficiency of the molten salt on the substrate, which accelerated the decontamination rate. Additionally, benefiting from the optimization of the experimental conditions by the response surface method (RSM), the decontamination efficiency was improved to 94.9%. Notably, it also showed remarkable results in the decontamination of specimens containing different uranium oxides at low and high levels of radioactivity. This technology is promising for broadening the path in rapid decontamination of radioactive contaminants on metal surfaces.

Conjugated Polymer Nanoparticles for Tumor Theranostics.

Water-dispersible conjugated polymer nanoparticles (CPNs) have demonstrated great capabilities in biological applications, such as in vitro cell/subcellular imaging and biosensing, or in vivo tissue imaging and disease treatment. In this review, we summarized the recent advances of CPNs used for tumor imaging and treatment during the past five years. CPNs with different structures, which have been applied to in vivo solid tumor imaging (fluorescence, photoacoustic, and dual-modal) and treatment (phototherapy, drug carriers, and synergistic therapy), are discussed in detail. We also demonstrated the potential of CPNs as cancer theranostic nanoplatforms. Finally, we discussed current challenges and outlooks in this field.

Melatonin: A potential adjuvant therapy for septic myopathy.

Septic myopathy, also known as ICU acquired weakness (ICU-AW), is a characteristic clinical symptom of patients with sepsis, mainly manifested as skeletal muscle weakness and muscular atrophy, which affects the respiratory and motor systems of patients, reduces the quality of life, and even threatens the survival of patients. Melatonin is one of the hormones secreted by the pineal gland. Previous studies have found that melatonin has anti-inflammatory, free radical scavenging, antioxidant stress, autophagic lysosome regulation, mitochondrial protection, and other multiple biological functions and plays a protective role in sepsis-related multiple organ dysfunction. Given the results of previous studies, we believe that melatonin may play an excellent regulatory role in the repair and regeneration of skeletal muscle atrophy in septic myopathy. Melatonin, as an over-the-counter drug, has the potential to be an early, complementary treatment for clinical trials. Based on previous research results, this article aims to critically discuss and review the effects of melatonin on sepsis and skeletal muscle depletion.

Targeting Proinflammatory Molecules Using Multifunctional MnO Nanoparticles to Inhibit Breast Cancer Recurrence and Metastasis.

Photothermal therapy (PTT) is an effective treatment modality that is highly selective for tumor suppression and is a hopeful alternative to traditional cancer therapy. However, PTT-induced inflammatory responses may result in undesirable side effects including increased risks of tumor recurrence and metastasis. Here we developed multifunctional MnO nanoparticles as scavengers of proinflammatory molecules to alleviate the PTT-induced inflammatory response. The MnO nanoparticles improve the PTT therapy by (1) binding and scavenging proinflammatory molecules to inhibit the proinflammatory molecule-induced Toll-like receptors (TLR) activation and nuclear factor kappa B (NF-κB) signaling; (2) inhibiting activated macrophage-induced macrophage recruitment; and (3) inhibiting tumor cell migration and invasion. In vivo experimental results showed that further treatment with MnO nanoparticles after laser therapy not only inhibited the PTT-induced inflammatory response and primary tumor recurrence but also significantly reduced tumor metastasis due to the scavenging activity. These findings suggest that MnO nanoparticles hold the potential for mitigating the therapy-induced severe inflammatory response and inhibiting tumor recurrence and metastasis.

Photothermal/nitric oxide synergistic anti-tumour therapy based on MOF-derived carbon composite nanoparticles.

Conventional organic photothermal conversion reagents still face some challenges for their real applications, such as the requirement of carriers for in vivo transport, uncontrolled degradation during use, reduction in photothermal conversion efficiency by repeated exposure to a near-infrared laser, and so on. Herein, uniform ZIF-8 nanoparticles were prepared first, and then carbonized and etched to form porous carbon nanoparticles (CNPs). After loading an NO donor and wrapping with red blood cell membrane, the novel CNP-NO@RBC photothermal agent integrated with in situ imaging ability was obtained. Due to the great photothermal conversion efficiency of the carbon material and the specific release of NO from the loaded NO conformer, the CNP-NO@RBCs show excellent tumour cell killing ability based on light-triggered photothermal/gas therapy at lower doses of CNP-NO@RBCs.

High-concentration COD wastewater treatment with simultaneous removal of nitrogen and phosphorus by a novel Candida tropicalis strain: Removal capability and mechanism.

Aerobic and anaerobic continuous stirred-tank reactor (CSTR), up-flow anaerobic sludge blanket (UASB) were set up and inoculated with newly isolated Candida tropicalis. Reactors were operated at high concentrations of chemical oxygen demand (COD) (8000 mg/L), the modified UASB expressed better COD removal rate simultaneously removal of nitrogen and phosphate than other two reactors. Notably, under both aerobic or anaerobic conditions, large amounts of organic acids and alcohol were generated. Transcriptomic analysis showed that carbon metabolism under anaerobic conditions shared the same pathway with aerobic conditions by regulating and inhibiting some functional genes. Experiments utilizing different carbon sources proved that our strain has excellent performances in utilizing organic materials, which were verified by transcriptomic analysis. Finally, the strain was applied to treat four types of sugar-containing wastewaters. Among them, our strain exerts the best removal capability of COD (90%), nitrogen (89%), and phosphate (82%) for brewery wastewater.

Overexpression of sesame polyketide synthase A leads to abnormal pollen development in Arabidopsis.

BACKGROUND: Sesame is a great reservoir of bioactive constituents and unique antioxidant components. It is widely used for its nutritional and medicinal value. The expanding demand for sesame seeds is putting pressure on sesame breeders to develop high-yielding varieties. A hybrid breeding strategy based on male sterility is one of the most effective ways to increase the crop yield. To date, little is known about the genes and mechanism underlying sesame male fertility. Therefore, studies are being conducted to identify and functionally characterize key candidate genes involved in sesame pollen development. Polyketide synthases (PKSs) are critical enzymes involved in the biosynthesis of sporopollenin, the primary component of pollen exine. Their in planta functions are being investigated for applications in crop breeding. RESULTS: In this study, we cloned the sesame POLYKETIDE SYNTHASE A (SiPKSA) and examined its function in male sterility. SiPKSA was specifically expressed in sesame flower buds, and its expression was significantly higher in sterile sesame anthers than in fertile anthers during the tetrad and microspore development stages. Furthermore, overexpression of SiPKSA in Arabidopsis caused male sterility in transgenic plants. Ultrastructural observation showed that the pollen grains of SiPKSA-overexpressing plants contained few cytoplasmic inclusions and exhibited an abnormal pollen wall structure, with a thicker exine layer compared to the wild type. In agreement with this, the expression of a set of sporopollenin biosynthesis-related genes and the contents of their fatty acids and phenolics were significantly altered in anthers of SiPKSA-overexpressing plants compared with wild type during anther development. CONCLUSION: These findings highlighted that overexpression of SiPKSA in Arabidopsis might cause male sterility through defective pollen wall formation. Moreover, they suggested that SiPKSA modulates vibrant pollen development via sporopollenin biosynthesis, and a defect in its regulation may induce male sterility. Therefore, genetic manipulation of SiPKSA might promote hybrid breeding in sesame and other crop species.

[Effect of moxibustion on quality of life in tumor patients: network Meta-analysis].

OBJECTIVE: To rank the effectiveness of various moxibustion methods on the quality of life in tumor patients, and explore the best treatment plan of moxibustion for improving the quality of life in tumor patients from the perspective of evidence-based medicine. METHODS: The Chinese and English literature of randomized controlled trial (RCT) of the effect of moxibustion on the quality of life in tumor patients were searched in PubMed, EMbase, Cochrane Library, CNKI, SinoMed, Wanfang and VIP. The retrieval time was from the establishment of the databases to October 31, 2020. The R3.6.2 and Stata15.0 software were used for network Meta-analysis based on Bayesian model. RESULTS: A total of 30 Chinese RCTs were included, including 2 169 patients, involving 16 interventions. In terms of the effectiveness of improving quality of life, the top three treatments were special moxibustion plus other therapies 1 (either of tendon acupuncture, acupoint pressing, acupoint injection, etc.), wheat-grain moxibustion and mild moxibustion. The special moxibustion methods were the combination of fire-dragon moxibustion, thunder-fire moxibustion, fuyang fire moxibustion and moxa salt-bag moxibustion. The number of literature of these four moxibustion methods was small. Considering the clinical application of moxibustion, it was concluded that wheat-grain moxibustion ranked first. CONCLUSION: The adjuvant treatment of wheat-grain moxibustion is more effective than other moxibustion methods on improving the quality of life in tumor patients, but the results needed to be further verified because the bias risk of RCT included in this study is high and the sample size is small.

Effects of different courses of moxibustion treatment on intestinal flora and inflammation of a rat model of knee osteoarthritis.

OBJECTIVE: This study was done to determine the effects of different courses of moxibustion on a rat knee osteoarthritis (KOA) model, and explore the dose-effect relationship of moxibustion on KOA from the perspectives of intestinal flora and inflammatory factors. METHODS: Wistar rats were randomly divided into five groups: normal, model, moxibustion for 2 weeks, moxibustion for 4 weeks and moxibustion for 6 weeks groups (n = 5 each group). A KOA rat model was induced by monosodium iodoacetate, and moxibustion intervention was performed at the acupoints "Dubi" (ST35) and "Zusanli" (ST36), once every other day. Pathologic changes in the cartilage of rat knee joints were assessed after intervention, and fecal samples were subjected to 16S rRNA high-throughput sequencing for microbial diversity analysis. RESULTS: Damage to the knee articular cartilage was obvious in the model group, which also had increased levels of pro-inflammatory factors, decreased levels of anti-inflammatory factors, and intestinal flora disorders with decreased diversity. The degree of cartilage damage in the 4 and 6 weeks of moxibustion groups was significantly improved compared with the model group. The 4 and 6 weeks of moxibustion groups also demonstrated reduced levels of interleukin-1ß and tumor necrosis factor-α and increased levels of interleukin-10 (P < 0.05). Both the abundance and diversity of the intestinal flora were increased, approaching those of the normal group. Abundances of probiotics Eubacterium coprostanoligenes group and Ruminococcaceae UCG-014 increased, while that of the pathogenic bacteria Lachnospiraceae NK4A136 group decreased (P < 0.05). Although the abundance of Lachnospiraceae NK4A136 group decreased in the 2 weeks of moxibustion group compared with the model group (P < 0.05), there was no statistically significant difference in serum inflammatory factors, flora species diversity or degree of pathological damage compared with the model group. CONCLUSION: Moxibustion treatment led to significant improvements in the intestinal flora and inflammatory factors of rats with KOA. Moxibustion treatment of 4 and 6 weeks led to better outcomes than the 2-week course. Moxibustion for 4 and 6 weeks can regulate intestinal flora dysfunction with increased probiotics and reduced pathogenic bacteria, reduce pro-inflammatory factors and increase anti-inflammatory factors. No significant differences were seen between the effects of moxibustion for 4 weeks and 6 weeks.

In vitro and in silico anti-osteoporosis activities and underlying mechanisms of a fructan, ABW90-1, from Achyranthes bidentate.

Achyranthes bidentata is a traditional Chinese medicine used to treat osteoporosis. AB90, a crude saccharide from A. bidentata, showed excellent osteoprotective effects in ovariectomized rats, and ABW90-1, an oligosaccharide purified from AB90, stimulated significant differentiation of osteoblasts. However, the osteogenic effects and underlying mechanisms of ABW90-1 have remained unknown. In the present study, we found that ABW90-1 significantly promoted ALP activity, mineralization, and the expression of osteogenic markers in MC3T3-E1 cells. ABW90-1 showed strong binding with the WNT signaling complex and BMP2 based on number of interactions, hydrogen bond length, and binding energy in silico. ABW90-1 significantly increased the expression of active-ß-catenin, p-GSK-3ß, LEF-1, BMP2, and p-SMAD1. Importantly, the osteogenic effects of ABW90-1 were partially suppressed by DKK-1 and Noggin, which are specific inhibitors of the WNT and BMP signaling pathways, respectively. Collectively, these findings suggest that ABW90-1 has osteogenic effects through crosstalk between WNT/ß-catenin and BMP2/SMAD1 signaling pathways.

Selenium-containing nanoparticles synergistically enhance Pemetrexed&NK cell-based chemoimmunotherapy.

NK cell-based immunotherapy and pemetrexed (Pem)-based chemotherapy have broad application prospects in cancer treatment. However, the over-expressed NK cell inhibitory receptor on the surface of cancer cells and the low cell internalization efficiency of Pem greatly limit their clinical application. Herein, we construct a series of selenium-containing nanoparticles to synergistically enhance Pem-based chemotherapy and NK cell-based immunotherapy. The nanoparticles could deliver Pem to tumor sites and strengthen the chemotherapy efficiency of Pem by seleninic acid, which is produced by the oxidation of ß-seleno ester. Moreover, seleninic acid can block the expression of inhibitory receptors against NK cells, thereby activating the immunocompetence of NK cells. The in vitro and in vivo experiments reveal the potential chemo-enhancing and immune-activating mechanism of seleninic acid, emphasizing the promising prospects of this strategy in effective chemoimmunotherapy.

Sesame ß-ketoacyl-acyl carrier protein synthase I regulates pollen development by interacting with an adenosine triphosphate-binding cassette transporter in transgenic Arabidopsis.

Male gametogenesis is an important biological process critical for seed formation and successful breeding. Understanding the molecular mechanisms of male fertility might facilitate hybrid breeding and increase crop yields. Sesame anther development is largely unknown. Here, a sesame ß-ketoacyl-[acyl carrier protein] synthase I (SiKASI) was cloned and characterized as being involved in pollen and pollen wall development. Immunohistochemical analysis showed that the spatiotemporal expression of SiKASI protein was altered in sterile sesame anthers compared with fertile anthers. In addition, SiKASI overexpression in Arabidopsis caused male sterility. Cytological observations revealed defective microspore and pollen wall development in SiKASI-overexpressing plants. Aberrant lipid droplets were detected in the tapetal cells of SiKASI-overexpressing plants, and most of the microspores of transgenic plants contained few cytoplasmic inclusions, with irregular pollen wall components embedded on their surfaces. Moreover, the fatty acid metabolism and the expression of a sporopollenin biosynthesis-related gene set were altered in the anthers of SiKASI-overexpressing plants. Additionally, SiKASI interacted with an adenosine triphosphate (ATP)-binding cassette (ABC) transporter. Taken together, our findings suggested that SiKASI was crucial for fatty acid metabolism and might interact with ABCG18 for normal pollen fertility in Arabidopsis.

Structural characterization and osteogenic activity in vitro of novel polysaccharides from the rhizome of Polygonatum sibiricum.

Polygonatum sibiricum Red., a kind of edible and medicinal plant, has a long history of use in traditional Chinese medicine and as a nutritional food additive. Water-soluble crude polysaccharide (PS50) was obtained from P. sibiricum rhizome. After deproteinization and dialysis, PS50 was isolated and purified via DEAE-52 cellulose and Sephadex G-75 gel filtration chromatography to obtain two novel polysaccharides (PSP50-2-1 and PSP50-2-2). Chemical analysis and nuclear magnetic resonance (NMR) studies indicated that PSP50-2-1 was composed of ß-d-Glcp-(1→, →2)-ß-d-Galp-(1→, →2,6)-ß-d-Galp-(1→, ß-d-Fruf-(2→, and PSP50-2-2 was composed of ß-d-Glcp-(1→, ß-d-Galp-(1→, →2)-ß-d-Galp-(1→, →6)-ß-d-Galp-(1→, →2,6)-ß-d-Galp-(1→, ß-d-Fruf-(2→. The morphological analysis suggested that PSP50-2-1 and PSP50-2-2 both had a rough surface with cracks. Pharmacological studies showed that PSP50-2-2 at concentrations of 2.59 and 5.19 µM significantly promoted the differentiation and mineralization of MC3T3-E1 cells in vitro, which indicated that PSP50-2-2 had a function of osteogenic activity. Above all, this study provides evidence that PSP50-2-2 may be used as an anti-osteoporotic agent, with applications in health-care and pharmaceutical industries.

Structural characterization and in vitro osteogenic activity of ABPB-4, a heteropolysaccharide from the rhizome of Achyranthes bidentata.

Achyranthes bidentata is a species of flowering plant that is mainly distributed in China. The A. bidentata rhizome is a famous traditional Chinese medicine that has been widely used to treat lumbago, arthritis, and bone hyperplasia. In this work, A. bidentata rhizome was isolated and purified to obtain a pectic polysaccharide (ABPB-4). Chemical and spectral analyses showed that ABPB-4 had a main chain of →4)-α-d-GalpA-(1→ and →2,4)-α-l-Rhap-(1→, and the branch chains included →4)-ß-d-Galp-(1→, →6)-ß-d-Galp-(1→, →3,6)-ß-d-Galp-(1→, →5)-α-l-Araf-(1→ and →3,5)-α-l-Araf-(1→, and it was terminated with α-l-Araf-(1→ and ß-d-Galp-(1→. At concentrations of 0.01, 0.02, and 0.04 µmol/L, ABPB-4 significantly promotes the proliferation, differentiation, and mineralization of MC3T3-E1 cells in vitro, and it appreciably enhances the mRNA expression levels of osteogenic-related genes in these cells. Overall, the results reported herein indicate that ABPB-4 has outstanding osteogenic activity, and that it may be used as an anti-osteoporosis agent in the future.

Structural elucidation and osteogenic activity of a novel heteropolysaccharide from Alhagi pseudalhagi.

Alhagi pseudalhagi, commonly known as camel thorn, is used as an indigenous medicinal plant in China. The present study was designed to elucidate the structure of a novel polysaccharide, APP90-2, isolated from Alhagi pseudalhagi and evaluate its osteogenic activity. A homogeneous polysaccharide (APP90-2) was obtained from A. pseudalhagi via DEAE-52 and Sephacryl S-100 columns, with a molecular weight of 5.9 kDa. Monosaccharide, GC-MS, and NMR analyses showed that APP90-2 consisted of α-l-Rhap-(1→, →3)-α-l-Araf-(1→, →5)-α-l-Araf-(1→, →4)-ß-d-Xylp-(1→, α-d-Glcp-(1→, →3,5)-α-l-Araf-(1→, →4)-ß-d-GlcAp-(1→, →4)-3-OAc-α-d-Glcp-(1→, →3)-α-d-Galp-(1→, →3)-ß-d-GalAp-(1→, →4)-α-d-Galp-(1→, →6)-α-d-Manp-(1→, →4,6)-ß-d-Galp-(1→, and →3,6)-ß-d-Glcp-(1→ with relative molar ratios of 4.1:1.8:6.1:6.7:1.7:1.0:1.5:2.7:2.4:1.1:2.3:2.6:1.4:2.0. Morphological analyses revealed that APP90-2 interacted with Congo-red and had an obvious honeycomb structure. Additionally, APP90-2 significantly promoted proliferation, differentiation, and mineralization of MC3T3-E1 cells, indicating that APP90-2 exhibited pronounced osteogenic activity. Therefore, our findings suggest that A. pseudalhagi may be used as an alternative medicine or health supplement for the prevention and treatment of osteoporosis.

Biomimetic Diselenide-Bridged Mesoporous Organosilica Nanoparticles as an X-ray-Responsive Biodegradable Carrier for Chemo-Immunotherapy.

Chemotherapy causes off-target toxicity and is often ineffective against solid tumors. Targeted and on-demand release of chemotherapeutics remains a challenge. Here, cancer-cell-membrane-coated mesoporous organosilica nanoparticles (MONs) containing X-ray- and reactive oxygen species (ROS)-responsive diselenide bonds for controlled release of doxorubicin (DOX) at tumor sites are developed. DOX-loaded MONs coated with 4T1 breast cancer cell membranes (CM@MON@DOX) show greater accumulation at tumor sites and prolonged blood circulation time versus an uncoated control in mice bearing 4T1 orthotopic mammary tumors. Under low-dose X-ray radiation, the DOX-loaded MONs exhibit carrier degradation-controlled release via cleavage of diselenide bonds, resulting in DOX-mediated immunogenic cell death at the tumor site. Combination with a PD-L1 checkpoint blockade further enhances inhibition of tumor growth and metastasis with low systemic toxicity. Together, the findings show the promise of these biomimetic, radiation-responsive diselenide-bond-bridged MONs in chemo-immunotherapy.

[Changes of microcirculation in superficial tissues of acupoint regions of lower leg during menstrual cycle in healthy young girls].

OBJECTIVE: To observe changes of microcirculation in the superficial regions of acupoints of the three Yin meridians of foot during the menstrual cycle in young college students, so as to provide experimental evidence for explaining the saying of traditional Chinese medicine that acupoints reflect the state of physiological and pathological activities of the internal organs. METHODS: Ninety healthy female volunteer college students were recruited in the present study. The subjects were asked to take a supine position on an examination couch to expose the Yuan-primary acupoints Taixi (KI3), Taibai (SP3) and Taichong (LR3), and Xi-cleft acupoints Shuiquan (KI5), Diji (SP8) and Zhongdu (LR6) which are related to the uterus of the three Yin meridians of foot， the crossing acupoints of the three Yin meridians of foot Sanyinjiao (SP6), non-specific acupoint of the Spleen meridian Xuehai (SP10), non-related meridian acupoint Xuanzhong (GB39) and non-meridian-non-acupoint (being at the same level of GB39, between the Stomach and Gallbladder meridians on the lateral aspect of the lower leg). The laser speckle blood flow imaging technique was used to detect the state of microcirculation (average blood perfusion volume) during menstrual, follicular, ovulatory and luteal phases. RESULTS: The average blood perfusion volume (ABPV) of the right SP8 region was significantly lower in the menstrual phase than in the ovulation and luteal phases (P<0.05), and in the follicular phase than in the ovulation phase (P<0.05). In the left LR6 region, the ABPV was obviously lower in the menstrual period than in the follicular, ovulation and luteal phases (P<0.05). In the SP8, SP6, KI3 and KI5 regions, the ABPV was significantly higher in each of the 4 phases on the left side than on the right side (P<0.05). In the right GB39, the ABPV in each of the 4 phases was apparently higher on the right side than on the left side (P<0.05). In the SP10 region, the ABPV was considerably higher on the left side than on the right side in the ovulation period (P<0.05). The ABPV of SP3 in the menstrual phase and that of the non-acupoint in the luteal phase were significantly higher on the right side than on the left side (P<0.05). CONCLUSION: The blood perfusion of microcirculation in the superficial tissues of Xi-cleft acupoints SP8 and LR6 is obviously lower in the menstrual phase than in both of the ovulation and luteal phases in healthy young college students, which may specifically reflect the periodical activities of the uterus in the physiological state, and provide a basis of acupoint selection for menstrual healthy care.