N-containing phenolic compounds from Periplaneta americana with triple negative breast cancer inhibitory activity.

Eight previously undescribed compounds comprising pyrrole-2-carboxaldehyde derivatives, namely periplanpyrroles A-D (1-4), spirooxindole derivatives perispirooxindoles A (5) and B (6), and the phenolic compounds periplanetols G (7) and H (8), along with eight known compounds were isolated from the 70% ethanol extract of the whole bodies of Periplaneta americana. Their structures including absolute configurations were unambiguously identified by comprehensive spectroscopic analyses and computational methods. In addition, all compounds were evaluated for their activities against triple negative breast cancer in vitro. The wound healing assay revealed that 7, 9, and 11 significantly inhibit the migration of BT549 and MDA-MB-231 cells. Further observations made in Western blotting experiments showed that 7 could dose-dependently decrease the protein level of vimentin and N-cadherin in MDA-MB-231 and BT549 cells.

Natural exosome-like nanoparticles derived from ancient medicinal insect Periplaneta americana L. as a novel diabetic wound healing accelerator.

Along with the recognized therapeutic outcomes of regenerative medicine, extracellular vesicles and their exosome subsets have become an alternative option for wound healing. Periplaneta americana L. (PA), an ancient and traditional medicinal insect, has been around for 300 million years, and displays magic formidable vitality and environmental adaptive ability. The linkage between intrinsic amputation regeneration feature and the acknowledged wound healing medicinal benefit of PA has never been revealed. Herein, inspired by the ability of exosomes to participate in the interkingdom communication, we explored whether this effect was ascribed to PA derived exosome-like nanoparticles (PA-ELNs). PA-ELNs were extracted by differential velocity centrifugation approach and characterized by DLS, NTA and TEM. Their cargoes were analyzed by LC-MS/MS proteomics and small RNA-seq analysis. The wound healing activity was verified in vivo and in vitro. PA-ELNs with a concentration of 2.33x109±6.35x107 particles/mL exhibited a lipid bilayer-bound membrane structure with an average size of 104.7 nm. Furthermore, the miRNA cargoes in PA-ELNs participate in some wound healing related signal pathways such as TGF-beta, mTOR, and autophagy. As expected, the in vitro tests indicated that PA-ELNs were apt to be internalized in HUVECs, L929 and RAW 264.7 cells and contributed to cell proliferation and migration. Most importantly, we demonstrated that the topical administration of PA-ELNs could remarkably accelerate wound healing in a diabetic mouse model, and was involved in anti-inflammatory, re-epithelialization and autophagy regulation. This study provides clear evidence for the first time that PA-ELNs, as diabetic wound healing accelerators, are the "bioactive code" of this ancient medicinal insect.

Antioxidant, antibacterial, and anti-inflammatory Periplaneta americana remnant chitosan/polysaccharide composite film: In vivo wound healing application evaluation.

Periplaneta americana (P. americana), which is widely used for wound healing in China, produces a large amount of solid waste (P. americana remnant) after pharmaceutical production extraction. P. americana remnant chitosan (PAC) has a low molecular weight, low crystallinity, and easily modifiable structural properties. In this study, PAC and P. americana remnant polysaccharide (PAP) were used as raw materials to prepare a composite film (PAPCF). The good biocompatibility of the composite film was verified by cell proliferation assays and protein adsorption assays. The bioactivity of the composite film was assessed by antibacterial and in vivo/vitro antioxidant assays to evaluate its potential as a wound dressing. The wound healing experiment revealed that PAPCF improved wound closure and collagen deposition, decreased reactive oxygen species levels, and attenuated the inflammatory response, enabling rapid wound healing from the inflammatory phase to the proliferative phase in mice. Additionally, PAPCF was administered only once, reducing the chance of infection from multiple deliveries. In summary, this paper presents an easy-to-administer, cost-effective, and effective dressing candidate for wound treatment based on the environmental concept of resource reuse.

Chitosan electrospun nanofibers derived from Periplaneta americana residue for promoting infected wound healing.

Periplaneta americana has been used medicinally for years to treat a wide variety of skin lesions or ulcers. However, a sizable portion of the drug residues that are retained after extraction are routinely thrown away, thus posing a hazard to the environment and depleting resources. In this study, low molecular weight Periplaneta americana chitosan (LPCS) and high molecular weight Periplaneta americana chitosan (HPCS) were extracted from Periplaneta americana residue (PAR) based on the conventional acid-base method and two deacetylation methods. Moreover, the physicochemical properties and structural differences between the above two chitosan and commercial chitosan (CS) were compared using different methods. Next, two nanofibers comprising different ratios of Periplaneta americana chitosan (LPCS or HPCS), polyvinyl alcohol (PVA), and polyethylene oxide (PEO) were prepared and optimized. The above nanofibers exhibited excellent mechanical properties, antibacterial properties, and biocompatibility while facilitating wound healing in an infected rat whole-layer wound model by promoting wound closure, epithelialization, collagen deposition, and inflammation reduction. In brief, this study produced an effective and affordable wound dressing and offered a suggestion for the comprehensive utilization of Periplaneta americana residue.

Two glycoproteins from medicinal insect Periplaneta americana (L.) promote diabetic wound healing via macrophage polarization modulation.

Along with the increasing attempts to explore the wound healing effective substances of Periplaneta americana (L.) (PA), a medicinal insect in traditional Chinese medicine, researchers' attention turned to the endogenetic macromolecules, such as polysaccharides and peptides. Herein, we innovatively isolated two glycoproteins from PA, named PAGP-1 and PAGP-2, which were obtained by Cellulose DE-52 chromatography and purified by Sephadex G-100 gel in succession. The structural characterization of the two PAGPs were performed, including molecular weight, amino acid and monosaccharide composition, morphology analysis, FT-IR and 1H NMR analysis, CD spectroscopy, and glycosides linkage. As a result, two PAGPs belonged to O-glycopeptide bonds linked glycoproteins. The content of carbohydrate and protein of PAGP-1 was approximately 25.23% and 65.92% respectively, which of PAGP-2 was approximately 25.71% and 71.23%. Based on the remarkable anti-inflammatory effects of PAGPs on LPS-induced RAW264.7 cells, the topical administration of PAGP-1 and PAGP-2 could significantly accelerate full-thickness wound healing in diabetic mice, involving to alleviate the inflammation, increase the ratio of type I and type III collagen fibers, and promote the polarization of macrophages M1 to M2. In short, this study provides clear evidence that the glycoproteins would be the potential wound healing bioactive substances in PA.

Periplaneta americana L. a potential source of traditional medicine: chemometric analysis, in vitro and in silico study.

'Mayurbhanj is the ethnic dominant tribal population district in Odisha, India. The triabl's of Mayurbhanj depends on traditional medicines since time immemorial for health-related issues. Due to the imperative ethnic claim of traditional healers, the financial stringency of the patient community and the necessity to produce a better therapeutic effect has led to investigate ethno zoological sources and to find out the biochemical moiety responsible for the healing process. Considering the ethnic communities' acceptability of the zoological source as traditional medicine, the current evidence-based research study is conducted to investigate the biochemical moiety present in Periplaneta americana, responsible for therapeutic activity. The whole powdered Periplaneta americana was extracted using maceration techniques with n-hexane and methanol as solvent. The obtained extracts were subjected to GC-MS analysis to identify the biochemical moiety. To check the potential biological activity, an in-vitro antimicrobial test was carried out in both turbidimetry and a viable count method against E. coli. Moreover, the obtained biochemical molecules were exposed to in silico studies for their binding modes and their affinity using Discovery studio software. The major compounds were found to be hexadecanoic acid, methyl ester, n-hexadecanoic acid, oleic acid, octadecanoic acid along with other minor constituents. The maximum inhibitory activity of n-hexane and methanol extract against S. aureus at a concentration of 400 µg/mL was found to be 89 and 87%, respectively. The binding models of almost all identified compounds confer very good binding affinities with some key and strong non-covalent interactions with various amino acid residues of receptor active site pocket, which predict the compounds to be potent inhibitors of various infectious bacteria. These findings suggested that the hexane extract of P. americana could be exploited as a potential natural source. Communicated by Ramaswamy H. Sarma.

Identification of anti-hepatic fibrosis components in Periplaneta americana based on spectrum-effect relationship and chemical component separation.

Periplaneta americana (PA) is used as a traditional medicine for hepatic diseases such as hepatic fibrosis in China. However, the relationship between the corresponding therapeutic effect and the chemical composition is still unclear. In this study, spectrum-effect relationship and chemical component separation were used to discover the potential of anti-hepatic fibrosis components of PA. The fingerprints of 10 batches of samples were established using HPLC, and the anti-hepatic fibrosis effect was determined using HSC-T6 cells. The spectrum-effect relationship between common peaks and efficacy values was established using partial least squares analysis. Partial peaks in the fingerprints were identified, including X4 (9,12-heptadecanedenoic acid glyceride), X5 (nonadecanoic acid methyl ester), X6 (glyceryl oleate), X7 (13,16,19-eicosatrienoic acid), X9 (linoleic acid), X10 (9,12,15-octadecatrienoic acid glyceride), X12 (hexadecanoic acid), X13 (oleic acid), and X14 (octadecanoic acid), and their anti-hepatic fibrosis activity was tested to verify the results of spectrum-effect relationships. The results showed that X4 , X6 , X7 , and X10 were the active ingredients of PA. This work successfully identified the partial anti-hepatic fibrosis components of PA, which can be used to explain the material basis for the PA anti-hepatic fibrosis effect.

Characterization and diabetic wound healing benefits of protein-polysaccharide complexes isolated from an animal ethno-medicine Periplaneta americana L.

Periplaneta americana L. (PA), a type of animal medicine, has been widely used for wound healing in clinical settings. In order to further investigate the bioactive wound healing substances in PA, crude PA protein-polysaccharide complexes were further purified by cellulose DE-52 and Sephadex G100 chromatography in succession. Among these isolated fractions, two fractions eluted by 0.3 M and 0.5 M NaCl with the higher yield, respectively named PaPPc2 and PaPPc3 respectively, were chosen for the wound healing experiments. Mediated by HPGPC, amino acid and monosaccharide composition analysis, circular dichroism spectrum, glycosylation type, FT-IR, and 1H NMR analysis, the characterization of PaPPc2 and PaPPc3 was implemented. And then, the benefits of PaPPcs to promote cell proliferation, migration, and tube formation of HUVECs were determined in vitro, indicated these fractions would facilitate angiogenesis. Finally, as proof of concept, PaPPc2 and PaPPc3 were employed to accelerate the acute wounds of diabetic mice, involving in increase blood vessels and the amounts of angiogenesis-related cytokines (α-SMA, VEGF, and CD31). In short, this study provides an experimental basis to demonstrate the protein-polysaccharide complexes of Periplaneta americana L. as its wound healing bioactive substances.

Analysis of the resistance of small peptides from Periplaneta americana to hydrogen peroxide-induced apoptosis in human ovarian granular cells based on RNA-seq.

Apoptosis of ovarian granular cells is closely related with weakening fertility of women. Hence, resisting apoptosis of human ovarian granular cells is of important significance. According to previous studies, DAPI fluorescence staining experiment and Western Blot test of Caspase-3 demonstrate that small peptides from Periplaneta americana (SPPA) can improve hydrogen peroxide (H2O2) -induced apoptosis of human ovarian granular cells (KGN cells). However, the molecular mechanism of SPPA resistance against apoptosis of granular cells still remains unknown. In this study, key genes and signaling pathways for SPPA to resist H2O2-induced apoptosis of KGN cells were determined through transcriptome sequencing (RNA-seq). Experiments were divided into three groups, namely, the control group, H2O2 group and H2O2 + SPPA group. A total of 1196 differentially expressed genes (DEGs) were screened by comparing the control group and the H2O2 group, and 2805 DEGs were screened by comparing the H2O2 group and H2O2 + SPPA group. It is important to note that 87 overlapping genes were identified upregulating in H2O2 exposure, but downregulating in SPPA repair. Another 151 overlapping genes were identified downregulating in H2O2 exposure, but upregulating in SPPA repair. These 238 overlapping genes have significant enrichment in multiple KEGG pathways. Among them, 13 genes play significant roles in SPPA resistance process of cell apoptosis: EIF3D, RAN, UPF1 and EIF2B4 participate in RNA transport; ACTG1, SIPA1 and CTNND1 participate in Leukocyte transendothelial migration; S100A7, S100A9, RELA and IL17RE participate in IL-17 signaling pathway; BCL2L13, EIF2AK3 and RELA participate in Mitophapy-animal. Ten genes were selected for florescence quantitative PCR (qPCR) verification and the expression level was consistent with sequencing results. Finally, a control network of SPPA resistance against the H2O2-induced KGN cell apoptosis was built based on the target genes screened by the RNA-seq technology. This study provides a direction and some references to further understand the molecular mechanism of SPPA resistance against the H2O2-induced KGN cell apoptosis.

Periplaneta americana (Insecta: Blattodea) and organ fibrosis: A mini review.

Fibrosis is the end stage of many chronic inflammatory diseases and eventually leads to organ failure. Periplaneta americana (P. americana) is referred to as "the product of flesh and blood" in traditional Chinese medicine and has a wide range of therapeutic effects. Owing to the growing interest in this insect for its application in the treatment of tissue injury-healing disorders that induce organ fibrosis, it has attracted the interest of researchers. A literature search was performed using core collections of electronic databases, such as PubMed, Web of Science, China National Knowledge Infrastructure, and Wanfang, using the keywords given below and terms such as pharmacological and biochemical details of this insect. P. americana extracts presented a wide range of therapeutic and biological activities, including antifibrotic, antiinflammatory, antioxidative, and tissue repair activities. Emerging evidence suggests that P. americana extracts may improve scarring, pulmonary fibrosis, liver fibrosis, and kidney fibrosis through the regulation of fibroblast activation, cytokine secretion, and deposition of fibrin, indicating the potential role of P. americana as a therapeutic option for organ fibrosis. P. americana is a potential therapeutic agent for treating fibrosis. Further studies are required for a more in-depth characterization of the antifibrogenic mechanism of P. americana prior to its clinical application in the treatment of organ fibrosis. (Fig. 1).

Anticancer Activity of Periplanetasin-5, an Antimicrobial Peptide from the Cockroach Periplaneta americana.

Cockroaches live in places where various pathogens exist and thus are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the pro-apoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Moreover, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

Periplaneta americana peptide decreases apoptosis of pig-ovary granulosa cells induced by H2 O2 through FoxO1.

Oxidative stress can induce apoptosis of granulosa cells and lead to follicular atresia, thereby reducing the number of pigs giving birth. The aim of this study was to investigate the protective effect of Periplaneta americana peptide (PAP) on the apoptosis of the granulosa cells of pig ovaries (PGCs) induced by hydrogen peroxide (H2 O2 ) via FoxO1. PGCs were treated with H2 O2 to establish a cell apoptosis model. Cell viability was measured using the cell counting kit-8 (CCK-8) assay, and cell apoptosis was detected using flow cytometry. The malondialdehyde (MDA) level and nitric oxide (NO) content were detected to reflect the oxidative stress. Western blotting, qRT-PCR and overexpression were undertaken to determine the expression of FoxO1 and caspase-3, and immunofluorescence was used to detect FoxO1 in the nucleus and cytoplasm. PGCs were treated with 100 µM H2 O2 for 6 hr, which resulted in oxidative damage and apoptosis and an apoptosis rate for PGCs of 32.95%. Next, PGCs were treated with 400 µg/ml PAP for 24 hr to repair the apoptosis induced by H2 O2 . PAP improved cell viability in H2 O2 -stimulated PGCs, the increased MDA level and NO content caused by H2 O2 stimulation were reversed and the apoptotic rate of PGCs was reduced. The qRT-PCR and Western blotting results indicated that PAP decreased the H2 O2 -induced apoptosis and the expression of FoxO1 and caspase-3 in PGCs. The effect of PAP was the same following FoxO1 overexpression. FoxO1 was expressed in the nucleus when stimulated by H2 O2 or overexpression; however, it migrated to the cytoplasm following PAP treatment. PAP decreased the apoptosis of PGCs induced by H2 O2 by regulating FoxO1 expression and nuclear translocation.

The protective effect of small peptides from Periplaneta americana on hydrogen peroxide-induced apoptosis of granular cells.

This study investigates the protective effect of small peptides from Periplaneta americana (SPPA) on hydrogen peroxide (H2O2)-induced apoptosis of ovarian granular cells. H2O2 was applied to human ovarian granular cells (KGN cell strains). Cell viability was tested by cell counting Kit-8 (CCK-8). Cell apoptosis was tested by flow cytometry, and a cell apoptosis model was established. The model cells were treated with SPPA, and the cell survival rate was monitored using the CCK-8 method. The oxidative stress state of cells was examined using SOD, ROS, MDA, and NO kits. The protein expression levels of SIRT1, p53, and the apoptosis-related gene Caspase3 were measured using Western Blot methodology. Relative to the control group, cell viability declined significantly after the H2O2 treatment only (P < 0.01), while the apoptosis rate increased significantly (P < 0.01). The activity of SOD was weakened significantly (P < 0.01), while the cell levels of ROS, MDA, and NO increased dramatically (P < 0.01). Cell viability dramatically recovered (P < 0.01), and the SOD activity is hugely increased (P < 0.01) after SPPA treatment. In contrast, contents of ROS, MDA, and NO decreased sharply (P < 0.01), and significant dose-response relationships are characterized. Moreover, the H2O2 treatment group showed significantly downregulated expression of SIRT1 (P < 0.01) but significantly upregulated expressions of p53 and Caspase3 (P < 0.01) compared to the control group. Following the SPPA treatment of apoptosis cells, expression of SIRT1 increased significantly, while expressions of p53 and Caspase3 declined significantly (P < 0.01). This study suggests that SPPA inhibits H2O2-induced human KGN cell apoptosis through antioxidation, and the SIRT1/p53 signal pathway mediates the antioxidation.

Periplaneta americana Oligosaccharides Exert Anti-Inflammatory Activity through Immunoregulation and Modulation of Gut Microbiota in Acute Colitis Mice Model.

The incidence and prevalence of inflammatory bowel disorders (IBD) are increasing around the world due to bacterial infection, abnormal immune response, etc. The conventional medicines for IBD treatment possess serious side effects. Periplaneta americana (P. americana), a traditional Chinese medicine, has been used to treat arthritis, fever, aches, inflammation, and other diseases. This study aimed to evaluate the anti-inflammatory effects of oligosaccharides from P. Americana (OPA) and its possible mechanisms in vivo. OPA were purified and biochemical characterization was analyzed by HPGPC, HPLC, FT-IR, and GC-MS. Acute colitis mice model was established, the acute toxicity and anti-inflammatory activity were tested in vivo. The results showed OPA with molecular mass of 1.0 kDa were composed of 83% glucose, 6% galactose, 11% xylose, and the backbone was (1→4)-Glcp. OPA had potent antioxidant activities in vitro and significantly alleviated the clinical symptoms of colitis, relieved colon damage without toxic side effects in vivo. OPA exhibited anti-inflammatory activity by regulating Th1/Th2, reducing oxidative stress, preserving intestinal barrier integrity, and inhibiting TLR4/MAPK/NF-κB pathway. Moreover, OPA protected gut by increasing microbial diversity and beneficial bacteria, and reducing pathogenic bacteria in feces. OPA might be the candidate of complementary and alternative medicines of IBD with low-cost and high safety.

First In Situ X-ray Scattering Measurements of Insect Body Surface Lipids: American Cockroach.

In situ X-ray scattering measurements of insect body surface lipids were successfully attempted by using a synchrotron X-ray source. The temperature-dependent structural changes of the cuticular hydrocarbons covering the forewing of an American cockroach were able to be followed, which showed that the majority of the hydrocarbons were in a liquid state even far below the critical temperature of water transpiration through the body surface. The results clearly demonstrated that synchrotron radiation X-ray scattering has the potential to obtain the detailed information about the intact lipid structure and physical properties on insect body surfaces.

Insect Body Defence Reactions against Bee Venom: Do Adipokinetic Hormones Play a Role?

Bees originally developed their stinging apparatus and venom against members of their own species from other hives or against predatory insects. Nevertheless, the biological and biochemical response of arthropods to bee venom is not well studied. Thus, in this study, the physiological responses of a model insect species (American cockroach, Periplaneta americana) to honeybee venom were investigated. Bee venom toxins elicited severe stress (LD50 = 1.063 uL venom) resulting in a significant increase in adipokinetic hormones (AKHs) in the cockroach central nervous system and haemolymph. Venom treatment induced a large destruction of muscle cell ultrastructure, especially myofibrils and sarcomeres. Interestingly, co-application of venom with cockroach Peram-CAH-II AKH eliminated this effect. Envenomation modulated the levels of carbohydrates, lipids, and proteins in the haemolymph and the activity of digestive amylases, lipases, and proteases in the midgut. Bee venom significantly reduced vitellogenin levels in females. Dopamine and glutathione (GSH and GSSG) insignificantly increased after venom treatment. However, dopamine levels significantly increased after Peram-CAH-II application and after co-application with bee venom, while GSH and GSSG levels immediately increased after co-application. The results suggest a general reaction of the cockroach body to bee venom and at least a partial involvement of AKHs.

Azobenzene-diamides as Photopharmacological Ligands for Insect Ryanodine Receptor.

Photoresponsive ligands are powerful tool compounds for studying receptor function with spatiotemporal resolution. However, to the best of our knowledge, such a ligand is not available for the ryanodine receptor (RyR). Herein, we present a photochromic ligand (PCL) for insect RyR by decorating chlorantraniliprole (CHL) with photoswitchable azobenzene (AB). We demonstrated that one potent ligand, named ABCHL13, shows light-induced reversible trans-cis isomerization and 3.5-fold insecticidal activity decrease toward oriental armyworm (Mythimna separata) after UV-light irradiation, that is, trans-ABCH13 has higher activity than the cis-ABCH13. ABCHL13 enables optical control over intracellular Ca2+ release in dorsal unpaired median (DUM) neurons of M. separata and American cockroach (Periplaneta americana) and cardiac function of P. americana. Our results provide a first photopharmacological toolkit that is applicable to light-dependent regulation of RyR and heart beating.

A composite hydrogel loading natural polysaccharides derived from Periplaneta americana herbal residue for diabetic wound healing.

In view of the long medicinal use history of Periplaneta americana for manifold ulcer or skin wounds treatment, the comprehensive utilization value of P. americana herbal residue was evaluated. In this study, we isolated a polysaccharide fraction from P. americana herbal residue with the potential wound healing effect, named as PAP faction, based on our previous study and provided the structural and monosaccharide composition characterization. To improve the topical wound dressing property, a novel composite hydrogel consisting of PAP, carbomer 940 (CBM), carboxymethyl cellulose (CMC) with different ratios were prepared and optimized. Mediated by the physical crosslinking effect among these polymers, the composite hydrogel exhibited good three-dimensional network structures, good swelling and water retention capacity, moderate mechanical property in rheological test. And then, the good cytocompatibility of hydrogel was corroborated by 3T3 fibroblast proliferation assay. Finally, the composite hydrogel loading PAP has been proved to accelerate wound healing in diabetic rat models, by promoting wound closure, collagen deposition, M2 macrophages polarization and angiogenesis. In summary, this study would provide an effective and promising wound dressing candidate for the prevention and treatment of diabetic wound, based on the ecological concept of the comprehensive utilization of natural herbal resources.

Periplanetols A-F, phenolic compounds from Periplaneta americana with potent COX-2 inhibitory activity.

Six new compounds, periplanetols A - F (1-4, 6 and 7), a compound isolated from natural origin for the first time (5), and nine known ones (8-16) were isolated from the 70% ethanol extract of the whole bodies of Periplaneta americana. Their structures including absolute configurations were unambiguously identified by comprehensive spectroscopic analyses and computational methods. Biological evaluation toward COX-2 inhibition revealed that compounds 1, 2, and 10 could inhibit COX-2 activity with the IC50 values of 768.0 nM, 617.7 nM, and 599.5 nM respectively, indicating their potential in developping novel agents against inflammation related disorders.

Mechanistic evaluation of gastro-protective effects of KangFuXinYe on indomethacin-induced gastric damage in rats.

KangFuXinYe (KFX), the ethanol extract of the dried whole body of Periplaneta americana, is a well-known important Chinese medicine preparation that has been used to treat digestive diseases such as gastric ulcers for many years in China. However, its therapeutic effect and mechanism are not yet well understood. Thus, the aim of this study was to investigate the gastro-protective effects of KangFuXinYe (KFX) in indomethacin-induced gastric damage. Rats were randomly divided into six groups as follows: control, treated with indomethacin (35 mg·kg-1), different dosages of KFX (2.57, 5.14 and 10.28 mL·kg-1, respectively) plus indomethacin, and sucralfate (1.71 mL·kg-1) plus indomethacin. After treatment, rat serum, stomach and gastric homogenates were collected for biochemical tests and examination of histopathology firstly. Rat serum was further used for metabolomics analysis to research possible mechanisms. Our results showed that KFX treatment alleviated indomethacin-induced histopathologic damage in rat gastric mucosa. Meanwhile, its treatment significantly increased cyclooxygenase-1 (COX-1), prostaglandin E2 (PGE2) and epidermal growth factor (EGF) levels in rat serum and gastric mucosa. Moreover, KFX decreased cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) levels. Nine metabolites were identified which intensities significantly changed in gastric damage rats, including 5-hydroxyindoleacetic acid, indoxylsulfuric acid, indolelactic acid, 4-hydroxyindole, pantothenic acid, isobutyryl carnitine, 3-methyl-2-oxovaleric acid, sphingosine 1-phosphate, and indometacin. These metabolic deviations came to closer to normal levels after KFX intervention. The results indicate that KFX (10.28 mL·kg-1) exerts protective effects on indomethacin-induced gastric damage by possible mechanisms of action (regulating tryptophan metabolism, protecting the mitochondria, and adjusting lipid metabolism, and reducing excessive indomethacin).