PDGF-ß and IL-18 Expressions on Carcinoma Cervical by Rhodomyrtus tomentosa.

<b>Background and Objective:</b> Cervical cancer, along with lung and breast cancer, is one of Indonesia's most aggressive gynaecological diseases. <i>Rhodomyrtus tomentosa</i> has antioxidant and antiproliferative properties that could be developed into herbal medicines for molecular therapy. The IL-18 and PDGF-ß are tumour-promoting agent proteins that may be therapeutic targets for a variety of cancers that were investigated in this study. <b>Materials and Methods:</b> Rats were classified into five groups: Group C- is the control group, Group C+ is the cancer model group and Group RHO200 is the <i>Rhodomyrtus tomentosa</i> 100 mg¹ b.wt., rat group, Group RHO400 is the <i>Rhodomyrtus tomentosa</i> 200 mg¹ b.wt., rat group and Group RHO400 is the <i>Rhodomyrtus tomentosa</i> 400 mg¹ b.wt., rat group. The rats were dissected 30 days after receiving <i>Rhodomyrtus tomentosa</i>. Immunohistochemistry is used to stain cervical tissues. <b>Results:</b> The expression of IL-18 and PDGF-ß was significantly different (p<0.01). The IL-18 and PDGF-ß were most abundant at the lowest <i>Rhodomyrtus tomentosa</i> doses (100-200 mg kg¹ b.wt.), while they were least abundant at the 400 mg kg¹ b.wt., doses. Histological analysis revealed that the highest dose of IL-18 and PDGF-ß expression reduced abnormal tissue and the space between tumours, followed by several carcinoma cells that stopped growing. <b>Conclusion:</b> <i>Rhodomyrtus tomentosa</i> can be used as a herbal therapy to reduce the expression of PDGF-ß and IL-18 (two cancer marker agents).

Angelica dahurica promoted angiogenesis and accelerated wound healing in db/db mice via the HIF-1α/PDGF-ß signaling pathway.

Impaired angiogenesis is crucial for impeding the wound healing process in diabetic foot ulcers (DFUs). In this study, we found that Angelica dahurica (A. dahurica) stimulated angiogenesis and benefited wound healing in genetic mouse models of diabetes. In HUVECs, A. dahurica promoted cell proliferation and tube formation, which was accompanied by increased nuclear translocation of HIF-1α under hypoxic conditions and led to elevated PDGF-ß protein expression. A. dahurica activated the PI3K/AKT signaling pathway in human umbilical vein endothelial cells (HUVECs), which was abrogated by the PI3K inhibitor LY294002. Furthermore, the cellular expression of PDGF-ß decreased significantly after treatment with a HIF-1α-siRNA, and PDGF-ß expression was increased in HIF-1α-overexpressing cells. In a full-thickness cutaneous wound healing db/db mouse model, A. dahurica accelerated wound closure, which was reflected by a significantly reduced wound area and an increase in neovascularization, as well as by elevated PDGF-ß expression and increased capillary formation. In addition, A. dahurica activated the PI3K/AKT signaling pathway and enhanced HIF-1α synthesis in wounds. In summary, A. dahurica promoted angiogenesis of HUVECs in vitro by promoting signaling via the HIF-1α/PDGF-ß pathway, efficiently enhancing vascularization in regenerated tissue and facilitating wound healing in vivo. The results revealed that A. dahurica has potential as a therapy for vessel injury-related wounds.

Caffeine prevents prostaglandin E1-induced disturbances in respiratory control in neonatal rats: implications for infants with critical congenital heart disease.

Continuous infusion of prostaglandin E1 (PGE1) is used to maintain ductus arteriosus patency in infants with critical congenital heart disease, but it can also cause central apnea suggesting an effect on respiratory neural control. In this study, we investigated whether 1) PGE1 inhibits the various phases of the acute hypoxic ventilatory response (HVR; an index of respiratory control dysfunction) and increases apnea incidence in neonatal rats; and 2) whether these changes would be reversible with caffeine pretreatment. Whole body plethysmography was used to assess the HVR and apnea incidence in neonatal rats 2 h following a single bolus intraperitoneal injection of PGE1 with and without prior caffeine treatment. Untreated rats exhibited a biphasic HVR characterized by an initial increase in minute ventilation followed by a ventilatory decline of the late phase (~5th minute) of the HVR. PGE1 had a dose-dependent effect on the HVR. Contrary to our hypothesis, the lowest dose (1 µg/kg) of PGE1 prevented the ventilatory decline of the late phase of the HVR. However, PGE1 tended to increase postsigh apnea incidence and the coefficient of variability (CV) of breathing frequency, suggesting increased respiratory instability. PGE1 also decreased brainstem microglia mRNA and increased neuronal nitric oxide synthase (nNOS) and platelet-derived growth factor-ß (PDGF-ß) gene expression. Caffeine pretreatment prevented these effects of PGE1, and the adenosine A2A receptor inhibitor MSX-3 had similar preventative effects. Prostaglandin appears to have deleterious effects on brainstem respiratory control regions, possibly involving a microglial-dependent mechanism. The compensatory effects of caffeine or MSX-3 treatment raises the question of whether prostaglandin may also operate on an adenosine-dependent pathway.

miR-184 exhibits angiostatic properties via regulation of Akt and VEGF signaling pathways.

Corneal avascularity is critical for achieving transparency necessary for proper transmission of light to the lens and visual acuity. Although much is known about angiogenesis and angiostasis, the precise regulation of these processes in the cornea is unclear. MicroRNA (miR)-184, the most abundant corneal epithelial miRNA, has been suggested to function in corneal angiostasis by altering VEGF signaling; however, the mechanism(s) underlying this regulation have not been addressed. Using a combination of in vitro and in vivo assays to evaluate angiogenesis, we demonstrated that human limbal epithelial keratinocytes (HLEKs) engineered to overexpress miR-184 secreted lower amounts of angiogenic mitogens. Human dermal microvascular cells exposed to conditioned medium from miR-184-overexpressing HLEKs were less proliferative and failed to seal linear scratch wounds. The in vivo Matrigel plug assay showed that conditioned medium from miR-184-expressing HLEKs elicited a lesser degree of neovascularization compared with controls. We found that miR-184 directly targets and represses the proangiogenic factors, friend of Gata 2 (FOG2), platelet-derived growth factor (PDGF)-ß, and phosphatidic acid phosphatase 2b (PPAP2B). FOG2 regulates VEGF expression, whereas PDGF-ß and PPAP2B regulate Akt activity. By attenuating both VEGF and Akt signaling, miR-184 acts as a broad-spectrum negative regulator of corneal angiogenesis.-Park, J. K., Peng, H., Yang, W., Katsnelson, J., Volpert, O., Lavker, R. M. miR-184 exhibits angiostatic properties via regulation of Akt and VEGF signaling pathways.

Comparison of TGF-ß, PDGF, and CTGF in hepatic fibrosis models using DMN, CCl4, and TAA.

Three chemotoxins including dimethylnitrosamine (DMN), carbon tetrachloride (CCl4), and thioacetamide (TAA) are commonly used in hepatofibrotic models. We aimed to draw characteristics of histopathology and pro-fibrogenic cytokines including TGF-ß, PDGF and CTGF among three models. Rats were divided into six groups and intra-peritoneally injected with DMN (10 mg/kg, for three weeks, three consecutive days weekly), CCl4 (1.6 g/kg, for 10 weeks, twice weekly), TAA (200 mg/kg, for 12 weeks, twice weekly) or their corresponded treatment for each control group. The liver weights were decreased in DMN model, but not other models. Ascites were occurred as 3-, 2-, and 7-rats in DMN, CCl4, and TAA model, respectively. The lipid peroxidation was highest in CCl4 model, serum levels of liver enzymes were increased as similar severity. The hepatofibrotic alterations were remarkable in DMN and TAA model, but not CCl4 as evidenced by the Masson trichrome staining and hydroxyproline. The immunohistochemistry for α-SAM showed that the DMN model was most severely enhanced than other models. On the other hand, hepatic tissue levels of pro-fibrogenic cytokines including TGF-ß, PDGF, and CTGF were generally increased in three models, but totally different among models or measurement resources. Especially, serum levels of three cytokines were remarkably increased by CCl4 injection and CTGF levels in both hepatic tissue and serum were highest in CCl4 group. Our results firstly demonstrated comparative study for features of morphological finding and pro-fibrogenic cytokines in serum and hepatic protein levels among three models. Above results would be a helpful reference for hepatofibrotic studies.

Telocytes in human heart valves.

Valve interstitial cells (VICs) are responsible for maintaining the structural integrity and dynamic behaviour of the valve. Telocytes (TCs), a peculiar type of interstitial cells, have been recently identified by Popescu's group in epicardium, myocardium and endocardium (visit www.telocytes.com). The presence of TCs has been identified in atria, ventricles and many other tissues and organ, but not yet in heart valves. We used transmission electron microscopy and immunofluorescence methods (double labelling for CD34 and c-kit, or vimentin, or PDGF Receptor-ß) to provide evidence for the existence of TCs in human heart valves, including mitral valve, tricuspid valve and aortic valve. TCs are found in both apex and base of heart valves, with a similar density of 27-28 cells/mm(2) in mitral valve, tricuspid valve and aortic valve. Since TCs are known for the participation in regeneration or repair biological processes, it remains to be determined how TCs contributes to the valve attempts to re-establish normal structure and function following injury, especially a complex junction was found between TCs and a putative stem (progenitor) cell.

Hyperoxia-induced developmental plasticity of the hypoxic ventilatory response in neonatal rats: contributions of glutamate-dependent and PDGF-dependent mechanisms.

Rats reared in hyperoxia exhibit a sustained (vs. biphasic) hypoxic ventilatory response (HVR) at an earlier age than untreated, Control rats. Given the similarity between the sustained HVR obtained after chronic exposure to developmental hyperoxia and the mature HVR, it was hypothesized that hyperoxia-induced plasticity and normal maturation share common mechanisms such as enhanced glutamate and nitric oxide signaling and diminished platelet-derived growth factor (PDGF) signaling. Rats reared in 21% O2 (Control) or 60% O2 (Hyperoxia) from birth until 4-5 days of age were studied after intraperitoneal injection of drugs targeting these pathways. Hyperoxia rats receiving saline showed a sustained HVR to 12% O2, but blockade of NMDA glutamate receptors (MK-801) restored the biphasic HVR typical of newborn rats. Blockade of PDGF-ß receptors (imatinib) had no effect on the pattern of the HVR in Hyperoxia rats, although it attenuated ventilatory depression during the late phase of the HVR in Control rats. Neither nitric oxide synthase inhibitor used in this study (nNOS inhibitor I and l-NAME) altered the pattern of the HVR in Control or Hyperoxia rats. Drug-induced changes in the biphasic HVR were not correlated with changes in metabolic rate. Collectively, these results suggest that developmental hyperoxia hastens the transition from a biphasic to sustained HVR by upregulating glutamate-dependent mechanisms and downregulating PDGF-dependent mechanisms, similar to the changes underlying normal postnatal maturation of the biphasic HVR.

Development of renal renin-expressing cells does not involve PDGF-B-PDGFR-ß signaling.

Apart from their endocrine functions renin-expressing cells play an important functional role as mural cells of the developing preglomerular arteriolar vessel tree in the kidney. The recruitment of renin-expressing cells from the mesenchyme to the vessel wall is not well understood. Assuming that it may follow more general lines of pericyte recruitment to endothelial tubes we have now investigated the relevance of the platelet-derived growth factor (PDGF)-B-PDGFR-ß signaling pathway in this context. We studied renin expression in kidneys lacking PDGFR-ß in these cells and in kidneys with reduced endothelial PDGF-B expression. We found that expression of renin in the kidneys under normal and stimulated conditions was not different from wild-type kidneys. As expected, PDGFR-ß immunoreactivity was found in mesangial, adventitial and tubulo-interstitial cells but not in renin-expressing cells. These findings suggest that the PDGF-B-PDGFR-ß signaling pathway is not essential for the recruitment of renin-expressing cells to preglomerular vessel walls in the kidney.

TGF-ß1 up-regulates the expression of PDGF-ß receptor mRNA and induces a delayed PI3K-, AKT-, and p70(S6K) -dependent proliferative response in activated hepatic stellate cells.

BACKGROUND: Transforming growth factor beta 1 (TGF-ß1) is a pleiotropic cytokine that activates hepatic stellate cell (HSC) proliferation, but inhibits parenchymal cell proliferation. Therefore, we hypothesize that TGF-ß1 regulates HSC proliferation and elucidated its molecular action. METHODS: In order to elucidate the molecular mechanism whereby TGF-ß1 up-regulates platelet derived growth factor beta (PDGF-ß) receptor mRNA and induces a delayed proliferation of HSC, we used proliferation and apoptosis assays as well as RT-PCR, Western blot analysis, immunostaining, and flow cytometry in mouse and rat HSC. RESULTS: We show that TGF-ß1 markedly induces the proliferation of mouse HSC in culture with concomitant 2.1-fold (p < 0.001) stimulation in [(3) H]-thymidine incorporation into cellular DNA. This induction is maximal between 24 and 36 hours postcytokine exposure that is triggered by 7.6-fold (p < 0.001) up-regulation of PDGF-ß receptor mRNA and associated increase in PDGF-ß receptor protein after 48 hours. TGF-ß1-dependent HSC proliferation is mimicked by H2 O2 that is inhibited by catalase, implying that TGF-ß1 action is mediated via reactive oxygen species. HSC proliferation is blunted by PDGF-ß receptor-neutralizing antibody as well as by specific inhibitors of PI3 kinase (PI3K), AKT, and p70(S6K) , indicating that the action of TGF-ß1 involves the activation of PDGF-ß receptor via the PI3K/AKT/p70(S6K) signaling pathway. TGF-ß1 also induces a reorganization of actin and myosin filaments and cell morphology leading to the formation of palisades although their myosin and actin contents remained constant. These findings suggest that TGF-ß1-mediated oxidative stress causes the transdifferentiation of HSC and primes them for extracellular matrix (ECM) deposition and scar contraction. CONCLUSIONS: We conclude that liver injury up-regulates TGF-ß1 that inhibits parenchymal cell proliferation, but stimulates HSC proliferation leading to the production of ECM and type I collagen resulting in fibrosis.

Cyclooxygenase-2-prostaglandin E2-eicosanoid receptor inflammatory axis: a key player in Kaposi's sarcoma-associated herpes virus associated malignancies.

The role of cyclooxygenase-2 (COX-2), its lipid metabolite prostaglandin E2 (PGE2), and Eicosanoid (EP) receptors (EP; 1-4) underlying the proinflammatory mechanistic aspects of Burkitt's lymphoma, nasopharyngeal carcinoma, cervical cancer, prostate cancer, colon cancer, and Kaposi's sarcoma (KS) is an active area of investigation. The tumorigenic potential of COX-2 and PGE2 through EP receptors forms the mechanistic context underlying the chemotherapeutic potential of nonsteroidal anti-inflammatory drugs (NSAIDs). Although role of the COX-2 is described in several viral associated malignancies, the biological significance of the COX-2/PGE2/EP receptor inflammatory axis is extensively studied only in Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8) associated malignancies such as KS, a multifocal endothelial cell tumor and primary effusion lymphoma (PEL), a B cell-proliferative disorder. The purpose of this review is to summarize the salient findings delineating the molecular mechanisms downstream of COX-2 involving PGE2 secretion and its autocrine and paracrine interactions with EP receptors (EP1-4), COX-2/PGE2/EP receptor signaling regulating KSHV pathogenesis and latency. KSHV infection induces COX-2, PGE2 secretion, and EP receptor activation. The resulting signal cascades modulate the expression of KSHV latency genes (latency associated nuclear antigen-1 [LANA-1] and viral-Fas (TNFRSF6)-associated via death domain like interferon converting enzyme-like- inhibitory protein [vFLIP]). vFLIP was also shown to be crucial for the maintenance of COX-2 activation. The mutually interdependent interactions between viral proteins (LANA-1/vFLIP) and COX-2/PGE2/EP receptors was shown to play key roles in the biological mechanisms involved in KS and PEL pathogenesis such as blockage of apoptosis, cell cycle regulation, transformation, proliferation, angiogenesis, adhesion, invasion, and immune-suppression. Understanding the COX-2/PGE2/EP axis is very important to develop new safer and specific therapeutic modalities for KS and PEL. In addition to COX-2 being a therapeutic target, EP receptors represent ideal targets for pharmacologic agents as PGE2 analogues and their blockers/antagonists possess antineoplastic activity, without the reported gastrointestinal and cardiovascular toxicity observed with few a NSAIDs.