Genetic adaptation of skin pigmentation in highland Tibetans.

Strong ultraviolet (UV) radiation at high altitude imposes a serious selective pressure, which may induce skin pigmentation adaptation of indigenous populations. We conducted skin pigmentation phenotyping and genome-wide analysis of Tibetans in order to understand the underlying mechanism of adaptation to UV radiation. We observe that Tibetans have darker baseline skin color compared with lowland Han Chinese, as well as an improved tanning ability, suggesting a two-level adaptation to boost their melanin production. A genome-wide search for the responsible genes identifies GNPAT showing strong signals of positive selection in Tibetans. An enhancer mutation (rs75356281) located in GNPAT intron 2 is enriched in Tibetans (58%) but rare in other world populations (0 to 18%). The adaptive allele of rs75356281 is associated with darker skin in Tibetans and, under UVB treatment, it displays higher enhancer activities compared with the wild-type allele in in vitro luciferase assays. Transcriptome analyses of gene-edited cells clearly show that with UVB treatment, the adaptive variant of GNPAT promotes melanin synthesis, likely through the interactions of CAT and ACAA1 in peroxisomes with other pigmentation genes, and they act synergistically, leading to an improved tanning ability in Tibetans for UV protection.

Synthesis of Pseudostellaria heterophylla polysaccharide-gold nanocomposites and their antitumor effect through immunomodulation.

Polysaccharides from natural sources have an excellent immune function and low toxicity; however, their limitations such as short half-life and instability limit their sustained pharmacological activity. In this context, the combination of polysaccharides and nanotechnology have been developed to promote the stability and prolong the immune activities of polysaccharides. To synthesize and explore the antitumor effect and immunomodulatory activity of PHP-AuNPs. Polysaccharides extracted from Pseudostellaria heterophylla were used to synthesize gold nanocomposites (PHP-AuNPs), and their physicochemical properties and immunoregulatory effect in vitro and in vivo were analyzed. The PHP-AuNPs were green synthesized with high biosafety. PHP-AuNPs can activate macrophages in vitro and decrease the tumor weight and volume, whereas they increase the immune organ index in vivo. Besides, PHP-AuNPs showed a beneficial effect for maintaining the immune balance of CD4+/CD8+ T cells and modulating the release of cytokines such as TNF-α increase and IL-10 decrease in mice. All these results suggested that PHP-AuNPs exhibit a remarkable antitumor effect and stronger immunomodulatory activity than that of free PHP-1. RESEARCH HIGHLIGHTS: The P. heterophylla polysaccharide-gold nanocomposites (PHP-AuNPs) were synthesized and physicochemical properties were characterized. The cytotoxicity in vitro and immunomodulatory effects of PHP-AuNPs on macrophages were analyzed. The immune-antitumor effects in vivo of PHP-AuNPs have also been confirmed.

Weakened tanning ability is an important mechanism for evolutionary skin lightening in East Asians.

The evolution of light-skin pigmentation among Eurasians is considered as an adaptation to the high-latitude environments. East Asians are ideal populations for studying skin color evolution because of the complex environment of East Asia. Here, we report a strong selection signal for the pigmentation gene phenylalanine hydroxylase (PAH) in light-skinned Han Chinese individuals. The intron mutation rs10778203 in PAH is enriched in East Asians and is significantly associated with skin color of the back of the hand in Han Chinese males (P < 0.05). In vitro luciferase and transcription factor binding assays show that the ancestral allele of rs10778203 could bind to SMAD2 and has a significant enhancer activity for PAH. However, the derived T allele (the major allele in East Asians) of rs10778203 decreases the binding activity of transcription factors and enhancer activity. Meanwhile, the derived T allele of rs10778203 shows a weaker ultraviolet radiation response in A375 cells and zebrafish embryos. Furthermore, rs10778203 decreases melanin production in transgenic zebrafish embryos after ultraviolet B (UVB) treatment. Collectively, PAH is a potential pigmentation gene that regulates skin tanning ability. Natural selection has enriched the adaptive allele, resulting in weakened tanning ability in East Asians, suggesting a unique genetic mechanism for evolutionary skin lightening in East Asians.

Antitumor effect of a polysaccharide from Pseudostellaria heterophylla through reversing tumor-associated macrophages phenotype.

Tumor-associated macrophages (TAMs), which are predominant tumor-infiltrating immune cells in the tumor microenvironment, participate in promoting the occurrence and metastasis of tumor cells. Reprogramming TAMs has become a promising immunotherapeutic approach for novel cancer treatments. In this study, a homogeneous polysaccharide (PHP-1) was obtained from Pseudostellaria heterophylla, and its antitumor and immunological activities, as well as the underlying molecular mechanisms were explored. These findings suggested that PHP-1 can switch M2 macrophages to the M1 type, thereby promoting tumor cell apoptosis in vitro. In addition, PHP-1 can modulate the TAMs phenotype, maintain the CD4+/CD8+ lymphocyte balance, and exert antitumor effects in H22 tumor-bearing mice. Mechanistically, PHP-1 is recognized by the TLR4 receptor, promotes Ca2+ release, and activates the NF-κB and MAPK signaling pathways to reset the M2-type macrophages. These findings indicate that PHP-1 from P. heterophylla can function as a tumor immunotherapeutic modulator.

Green synthesized gold nanoparticles from Pseudobulbus Cremastrae seu Pleiones show efficacy against hepatic carcinoma potentially through immunoregulation.

Nanobiotechnology, the interface between biology and nanotechnology, has recently emerged in full bloom in the medical field due to its minimal side-effects and high efficiency. To broaden the application of nanobiotechnology, we composed gold nanoparticles from the extract of Pseudobulbus Cremastrae seu Pleiones (PCSP) using an efficient and green procedure. The biosynthesized Au nanoparticles containing PCSP (PCSP-AuNPs) were characterized by UV-vis spectroscopic, transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), and Energy Dispersive X-ray (EDAX). After verifying the stability of PCSP-AuNPs, we detected its biosafety and immune-modulatory effects on RAW264.7 in vitro using NO assay, ELISA (TNF-α, IL-12p70, and IL-1ß), and CCK-8 test. Furthermore, we examined the direct in vitro effects of PCSP-AuNPs on hepatocellular carcinomas (HCCs). Finally, we evaluated the immune regulation of PCSP-AuNPs using a mouse model with H22-tumor by testing the index of immune organs, splenic lymphocyte proliferation, cytokines levels (TNF-α and IL-10), and the CD4+/CD8+ cell ratio in the peripheral blood. Immunohistochemical analyses including H&E and PCNA staining were performed to investigate the anti-cancer efficacy and biocompatibility of PCSP-AuNPs. We found that PCSP-AuNPs not just possessed low toxicity, but also improved the immune-mediated antitumor response as compared to PCSP alone, suggesting its potential as a novel and efficient drug for liver cancer therapy.

Green synthesis and characterization of gold nanoparticles from Pholiota adiposa and their anticancer effects on hepatic carcinoma.

Gold nanoparticles (AuNPs) were successfully fabricated by Pholiota adiposa polysaccharide (PAP-1a) without employing any other chemicals. The physical and chemical properties of PAP-AuNPs were determined using transmission electron microscopy (TEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDXR), Fourier-transform infrared spectroscopy (FT-IR), and atomic force microscopy (AFM). In an attempt to analyze the immune regulation, antitumor effect, and biological safety, the production of NO and TNF-α, IL-12p70, and IL-1ß from RAW264.7 as well as the proliferation of RAW264.7 were detected in vitro. Flow cytometry was conducted to determine the ratio of the CD4+/CD8+ cell in peripheral blood and immunohistochemical analysis involving hematoxylin and eosin (H&E) and proliferating cell nuclear antigen (PCNA) staining were conducted in vivo. The results of this study showed that PAP-AuNPs had a significantly improved immune regulation and anti-tumor effect in comparison to PAP-1a alone. PAP-AuNPs showed no toxicity both in vivo and in vitro. This study demonstrates a useful application of PAP-AuNPs as a novel nanomedicine for hepatic carcinoma.

Study on the physicochemical properties and immunomodulatory anti-tumor effect of the Pholiota adiposa polysaccharide.

In this study, the extraction, purification, physical and chemical properties, and biological activity of the Pholiota adiposa (PAP) polysaccharide were investigated. One fraction (PAP-1a) of Pholiota adiposa polysaccharides was isolated using DEAE Sepharose™ Fast Flow and Sephacryl™ S-300 High-Resolution columns. The HPLGPC results revealed that the molecular weight of PAP-1a was 16.453 kDa. PAP-1a was composed of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose and their molar % was 33.41, 0.53, 1.33, 0.07, 0.27, 5.28, 38.31, 0.83, 18.04 and 2.23, respectively. PAP-1a could activate macrophages to secrete NO and cytokines such as TNF-a, IL-6, and IL-12p70. When hepatocellular carcinoma cells (HCCs) and macrophages were co-cultured, it was observed that PAP-1a inhibited the growth of Hep-G2, Hep-3B, and Huh7 via immunoregulation. It triggered cell apoptosis by blocking the cell cycle in the G0/G1 stage. Furthermore, PAP-1a had no direct cytotoxicity against the hepatocyte cell line L02 and macrophages RAW264.7.

Cloning and base editing of GFP transgenic rhesus monkey and off-target analysis.

We report the cloning of a 12-year-old transgenic green fluorescent protein (GFP) monkey by somatic cell nuclear transfer (SCNT) and base editing of the embryos, accompanied with safety evaluation of adenine base editors (ABEs). We first show the ability of ABEmax to silence GFP through A-to-G editing of the GFP sequence in 293T cells. Subsequently, using donor cells from a monkey expressing GFP, we have successfully generated 207 ABEmax-edited (SCNT-ABE) and 87 wild-type (SCNT) embryos for embryo transfer, genotyping, and genome and transcriptome analysis. SCNT-ABE and SCNT embryos are compared for off-target analysis without the interference of genetic variants using a new method named as OA-SCNT. ABEmax does not induce obvious off-target DNA mutations but induces widespread off-target RNA mutations, 35% of which are exonic, in edited monkey embryos. These results provide important references for clinical application of ABE.

Investigation of Potential Molecular Biomarkers for Diagnosis and Prognosis of AFP-Negative HCC.

BACKGROUND: Alpha-fetoprotein (AFP) is the most important diagnostic and prognostic index of hepatocellular carcinoma (HCC). AFP-positive HCC can be easily diagnosed based on the serum AFP level and typical imaging features, but a number of HCC patients are negative (AFP < 20 ng/mL) for AFP. Therefore, it is necessary to develop novel diagnostic and prognostic biomarkers for AFP-negative HCC. METHODS: RNA data from TCGA and differential expression of lncRNAs, miRNAs, and mRNAs were downloaded to analyze the differential RNA expression patterns between AFP-negative HCC tissues and normal tissues. A lncRNA-miRNA-mRNA ceRNA regulatory network was constructed to elucidate the interaction mechanism of RNAs. Functional enrichment analysis of these DEmRNAs was performed to indirectly reveal the mechanism of action of lncRNAs. A PPI network was built using STRING, and the hub genes were identified with Cytoscape. The diagnostic value of hub genes was assessed with receiver operating characteristic (ROC) analysis. And the prognostic value of RNAs in the ceRNA was estimated with Kaplan-Meier curve analysis. RESULTS: A total of 131 lncRNAs, 185 miRNA, and 1309 mRNAs were found to be differentially expressed in AFP-negative HCC. A ceRNA network consisting of 12 lncRNA, 23 miRNA, and 74 mRNA was constructed. The top ten hub genes including EZH2, CCNB1, E2F1, PBK, CHAF1A, ESR1, RRM2, CCNE1, MCM4, and ATAD2 showed good diagnostic power under the ROC curve; and 2 lncRNAs (LINC00261, LINC00482), 3 miRNAs (hsa-miR-93, hsa-miR-221, hsa-miR-222), and 2 mRNAs (EGR2, LPCAT1) were found to be associated with the overall survival of AFP-negative patients. CONCLUSION: This study could provide a novel insight into the molecular pathogenesis of AFP-negative HCC and reveal some candidate diagnostic and prognostic biomarkers for AFP-negative HCC.

Physicochemical properties of polysaccharides from Ligusticum chuanxiong and analysis of their anti-tumor potential through immunoregulation.

We investigated the extraction, purification, physicochemical properties and biological activity of Ligusticum chuanxiong polysaccharides (LCXPs). Two polysaccharide fractions (Ligusticum chuanxiong [LCX]P-1a and LCXP-3a) were obtained by DEAE Sepharose™ Fast Flow and Sephacryl™S-300 high resolution column chromatography. The results showed that the molecular weight of LCXP-1a and LCXP-3a was 11.159 kDa and 203.486 kDa, respectively. LCXP-1a is composed of rhamnose, glucuronic acid, galacturonic acid, and glucose at a molar percentage of 0.52 : 1.88 : 1.06 : 95.36, But LCXP-3a has another molar percentage of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose of 0.64 : 6.69 : 1.03 : 43.74 : 2.20 : 26.90 : 0.82 : 15.94 : 1.80. Both LCXP-1a and LCXP-3a could stimulate macrophages to produce NO, TNF-α, IL-6, and IL-12p70. Co-culturing macrophages and hepatocellular carcinoma cells showed that LCXP-1a and LCXP-3a inhibited the growth of HepG2 and Hep3B through immunoregulation. They arrested the cell cycle at the G0/G1 phase and promoted apoptosis. Moreover, there was no cytotoxicity to the hepatocyte cell line, LO2. We also noted that the immunomodulatory activity and anti-tumor activity of LCXP-3a were significantly better than those of LCXP-1a. Our data demonstrate that LCXP-3a is potentially a well-tolerated and effective immunomodulatory adjuvant cancer treatment.

Structure characteristics and immunomodulatory activities of a polysaccharide RGRP-1b from radix ginseng Rubra.

The present study was undertaken to explore the structure characteristics, immune regulation, and anti-cancer abilities of polysaccharides in radix ginseng Rubra (RGR). For this purpose, RGR polysaccharides (RGRP) were purified through DEAE and S-300 chromatography. Monosaccharide composition, methylation, and GC-MS analyses, as well as field emission scanning electron microscope (FESEM), atomic force microscope (AFM), Fourier-transformed infrared resonance (FT-IR), and nuclear magnetic resonance (NMR) spectra, were used to establish the structure of RGRP-1b. Our results revealed that RGRP-1a and RGRP-1b possess different molecular weights (21.3 kDa and 10.2 kDa, respectively). RGRP-1a was found to be composed of glucose, while RGRP-1b was composed of glucose, galactose, and arabinose. The main chain structure of RGRP-1b was composed of 1,4-α-Glcp, with a 1,4,6-α-Glcp branch unit. Its side chains were branched at the O-4 position of 1,4,6-α-Glcp, namely 1)-ß-Galp-(4 â†’ 1)-α-Araf-(5 â†’ α-Araf and 1)-ß-Galp-(6 â†’ α-Glcp. The changes in the nitric oxide (NO) levels and cytotoxicity revealed that macrophages probably get activated by RGRP-1b. The expressions of IL-6, IL-12, and TNF-α were found to be upregulated after treatment with RGRP-1b. RGRP-1b thus possesses the potential to arrest the growth of Huh7 through immunoregulation. Our cumulative findings indicate that RGRP-1b obtained from radix ginseng Rubra can function as a strong immune modulator.

Immunomodulatory effects of a polysaccharide from Solanum nigrum Linne through TLR4-MyD88 signaling pathway.

Solanum nigrum Linne polysaccharide (SNLP), an active ingredient from Solanum nigrum Linne, has been proposed to inhibit tumor growth and display immunomodulatory activity. However, the molecular mechanism related to immune regulation remains unclear. In the present study, a homogeneous polysaccharide (SNLP-1) was extracted, the immune effects and the underlying molecular mechanisms were investigated. The immunomodulatory activity assay in vitro showed that SNLP-1 promoted the release of NO and TNF-α and IL-6 secretion in macrophages. In tumor-bearing mice, SNLP-1 could improve immune function including increasing the spleen index, thymus index and inducing Th1 responses mediated by IL-2, IFN-γ, and TNF, as well as decreasing the tumor weight. Furthermore, SNLP-1 elevated the expression of the critical nodes in the TLR4-Myd88 signaling pathways in vitro and in vivo. These results indicated that TLR4-MyD88 signal pathway may be one of the signal pathways of immune regulation of SNLP-1.

Immunomodulatory effects exerted by Poria Cocos polysaccharides via TLR4/TRAF6/NF-κB signaling in vitro and in vivo.

OBJECTIVE: Poria cocos polysaccharide (PCP) is the major active ingredients of P. cocos and possesses various pharmacological effects, including anti-oxidative and anti-apoptosis effects and activity against cancer. This study investigated the immunomodulatory mechanism by which PCP acts on RAW 264.7 macrophages and LLC tumors in mice. METHODS: The concentrations of nitric oxide, and Th1, Th2, and Th17 cytokines were examined by Griess reaction and using a bead-based cytokine assessment kit. qRT-PCR and western blotting were used to investigate relevant signaling molecule expression. RESULTS: Levels of nitric oxide, IL-2, IL-6, IL-17 A, TNF, and IFN-γ were increased by PCP while levels of IL-4 and IL-10 were unaffected. The addition of TAK-242 (TLR4 inhibitor) or assessment in C57BL/10ScNJ (TLR4-deficient) mice markedly reduced this effect. In C57BL/10 J (TLR4+/+wild-type) mice, the indices of organ immune activity were all elevated, and oral PCP delivery resulted in a significant reduction in tumor volume over a 25 day period. Relative to controls, TLR4, MyD88, TRAF-6, p-NF-κB and p-c-JUN expression significantly increased, while TRAM expression did not change. Nevertheless, there was no PCP-dependent activation of MyD88, TRAF-6, TRAM, p-NF-κB or p-c-JUN in TLR4-deficient mice. CONCLUSION: These results support the concept that PCP may exhibit immunomodulatory activity through TLR4/TRAF6/NF-κB signaling both in vitro and in vivo.

The immunomodulatory effect of Poria cocos polysaccharides is mediated by the Ca2+/PKC/p38/NF-κB signaling pathway in macrophages.

Poria cocos polysaccharide (PCP), extracted from Poria cocos sclerotium, has many biological activities. The present study explored the immunomodulatory effect and the underlying molecular mechanism of PCP in RAW 264.7 macrophages. Griess reaction, ELISA assays and confocal laser scanning microscopy revealed that the production of nitric oxide (NO), TNF-α, IL-1ß, IL-6 and intracellular calcium level were increased by PCP. However, this effect on cytokines was suppressed with a Ca2+ channel blocker or a p38 inhibitor, which indicates that Ca2+ and p38 are crucial to the immunomodulatory effect of PCP. We further demonstrated that PCP-treated cells also exhibited increased the activity of PKC, mRNA and protein expression levels of p38 and NF-κB, which is also reduced with a Ca2+ channel blocker. Taken together, the Ca2+/PKC/p38/NF-κB signaling pathway may involve in the immunomodulatory effects of PCP.