Role of the endoscopic Doppler probe in nonvariceal upper gastrointestinal bleeding: Systematic review and meta-analysis.

OBJECTIVES: The effectiveness of the Doppler endoscopic probe (DEP) remains unclear in nonvariceal upper gastrointestinal bleeding (NVUGIB). We thus performed a systematic review characterizing the effectiveness of DEP in patients with NVUGIB addressing this question. METHODS: A literature search was done until July 2021 using MEDLINE, EMBASE, and ISI Web of Science. A series of meta-analyses were performed assessing outcomes among observational and interventional studies for DEP signal positive and negative lesions as well as DEP-assisted versus standard endoscopies. The primary outcome was "overall rebleeding"; secondary outcomes included all-cause mortality, bleeding-related mortality, need for surgery, length of stay, intensive care unit stay, and angiography. RESULTS: Fourteen studies were included from 1911 citations identified. Observational studies compared bleeding lesions with DEP-positive versus DEP-negative signals (11 studies, n = 800 prehemostasis; five studies, n = 148 with posthemostasis data). Three interventional studies (n = 308) compared DEP-assisted to standard endoscopy management. DEP signal positive versus negative lesions either prior to or following any possible hemostasis were at greater risk of overall rebleeding (odds ratio [OR] 6.54 [2.36, 18.11] and OR 25.96 [6.74, 100.0], respectively). The use of DEP during upper endoscopy significantly reduced overall rebleeding rates (OR 0.27 [0.14, 0.54]). When removing outcomes analysis for which only one study was available, all evaluable outcomes were improved with DEP characterization of management guidance except for all-cause mortality. CONCLUSION: Although with low certainty evidence, DEP-related information improves on sole visual prediction of rebleeding in NVUGIB, with DEP-guided management yielding decreased overall rebleeding, bleeding-related mortality, and need for surgery.

Exome sequencing allows detection of relevant pharmacogenetic variants in epileptic patients.

Beyond the identification of causal genetic variants in the diagnosis of Mendelian disorders, exome sequencing can detect numerous variants with potential relevance for clinical care. Clinical interventions can thus be conducted to improve future health outcomes for patients and their at-risk relatives, such as predicting late-onset genetic disorders accessible to prevention, treatment or identifying differential drug efficacy and safety. To evaluate the interest of such pharmacogenetic information, we designed an "in house" pipeline to determine the status of 122 PharmGKB (Pharmacogenomics Knowledgebase) variant-drug combinations in 31 genes. This pipeline was applied to a cohort of 90 epileptic patients who had previously an exome sequencing (ES) analysis, to determine the frequency of pharmacogenetic variants. We performed a retrospective analysis of drug plasma concentrations and treatment efficacy in patients bearing at least one relevant PharmGKB variant. For PharmGKB level 1A variants, CYP2C9 status for phenytoin prescription was the only relevant information. Nineteen patients were treated with phenytoin, among phenytoin-treated patients, none were poor metabolizers and four were intermediate metabolizers. While being treated with a standard protocol (10-23 mg/kg/30 min loading dose followed by 5 mg/kg/8 h maintenance dose), all identified intermediate metabolizers had toxic plasma concentrations (20 mg/L). In epileptic patients, pangenomic sequencing can provide information about common pharmacogenetic variants likely to be useful to guide therapeutic drug monitoring, and in the case of phenytoin, to prevent clinical toxicity caused by high plasma levels.

Clinical and neuroimaging findings in 33 patients with MCAP syndrome: A survey to evaluate relevant endpoints for future clinical trials.

Megalencephaly-CApillary malformation-Polymicrogyria (MCAP) syndrome results from somatic mosaic gain-of-function variants in PIK3CA. Main features are macrocephaly, somatic overgrowth, cutaneous vascular malformations, connective tissue dysplasia, neurodevelopmental delay, and brain anomalies. The objectives of this study were to describe the clinical and radiological features of MCAP, to suggest relevant clinical endpoints applicable in future trials of targeted drug therapy. Based on a French collaboration, we collected clinical features of 33 patients (21 females, 12 males, median age of 9.9 years) with MCAP carrying mosaic PIK3CA pathogenic variants. MRI images were reviewed for 21 patients. The main clinical features reported were macrocephaly at birth (20/31), postnatal macrocephaly (31/32), body/facial asymmetry (21/33), cutaneous capillary malformations (naevus flammeus 28/33, cutis marmorata 17/33). Intellectual disability was present in 15 patients. Among the MRI images reviewed, the neuroimaging findings were megalencephaly (20/21), thickening of corpus callosum (16/21), Chiari malformation (12/21), ventriculomegaly/hydrocephaly (10/21), cerebral asymmetry (6/21) and polymicrogyria (2/21). This study confirms the main known clinical features that defines MCAP syndrome. Taking into account the phenotypic heterogeneity in MCAP patients, in the context of emerging clinical trials, we suggest that patients should be evaluated based on the main neurocognitive expression on each patient.

Ten-year experience with arterial embolization for peptic ulcer bleeding: N-butyl cyanoacrylate glue versus other embolic agents.

OBJECTIVES: To compare our experience with N-butyl cyanoacrylate glue as the primary embolic agent versus other embolic agents for transcatheter arterial embolization (TAE) in refractory peptic ulcer bleeding and to identify factors associated with early rebleeding and 30-day mortality. METHODS: Retrospective study of 148 consecutive patients comparing the clinical success rate in 78 patients managed with Glubran®2 N-butyl cyanoacrylate metacryloxysulfolane (NBCA-MS) alone or with other agents and 70 with other embolic agents only (coils, microspheres, ethylene-vinyl alcohol copolymer, or gelatin sponge) at a university center in 2008-2019. Univariate and multivariate logistic regression analyses were done to identify prognostic factors. RESULTS: The technical success rate was 95.3% and the primary clinical success was 64.5%. The early rebleeding and day-30 mortality rates were 35.4% and 21.3%, respectively. Rebleeding was significantly less common with than without Glubran®2 (OR, 0.47; 95% CI, 0.22-0.99; p = .047) and significantly more common with coils used alone (OR, 20.4; 95% CI, 10.13-50.14; p = .024). The only other factor independently associated with early rebleeding was having two or more comorbidities (OR, 20.14; 95% CI, 10.01-40.52; p = .047). Day-30 mortality was similar in the two treatment groups. A lower initial hemoglobin level was significantly associated with higher day-30 mortality (OR, 10.38; 95% CI, 10.10-10.74; p = .006). Fluoroscopy time was significantly shorter with Glubran®2 (20.8 ± 11.5 min vs. 35.5 ± 23.4 min, p = .002). Both groups (Glubran®2 vs. other agents) had similar rates of overall complications (10.7% vs. 9.1%, respectively, p = .786). CONCLUSIONS: Glubran®2 NBCA-MS as the primary agent allowed for faster and better clinical success compared to other embolic agents when used for TAE to safely stop refractory peptic ulcer bleeding. KEY POINTS: • Choice of embolic agent for arterial embolization of refractory peptic ulcer bleeding is still debated. We compared our experience with N-butyl cyanoacrylate (NBCA) glue vs. other embolic agents. • The use of Glubran®2 NBCA glue in the endovascular management of refractory peptic ulcer bleeding was significantly faster and more effective, and at least as safe compared to other embolic agents. • NBCA glue offers several advantages compared to other embolic agents and provides rapid hemostasis when used for arterial embolization to treat refractory peptic ulcer bleeding. It should be the first-line therapy.

Recent advances in clinical practice: colorectal cancer chemoprevention in the average-risk population.

Colorectal cancer (CRC) is one of the most common and lethal malignancies in Western countries. Its development is a multistep process that spans more than 15 years, thereby providing an opportunity for prevention and early detection. The high incidence and mortality rates emphasise the need for prevention and screening. Many countries have therefore introduced CRC screening programmes. It is expected, and preliminary evidence in some countries suggests, that this screening effort will decrease CRC-related mortality rates. CRC prevention involves a healthy lifestyle and chemoprevention-more specifically, oral chemoprevention that can interfere with progression from a normal colonic mucosa to adenocarcinoma. This preventive effect is important for individuals with a genetic predisposition, but also in the general population. The ideal chemopreventive agent, or combination of agents, remains unknown, especially when considering safety during long-term use. This review evaluates the evidence across 80 meta-analyses of interventional and observational studies of CRC prevention using medications, vitamins, supplements and dietary factors. This review suggests that the following factors are associated with a decreased incidence of CRC: aspirin, non-steroidal anti-inflammatory drugs, magnesium, folate, a high consumption of fruits and vegetables, fibre and dairy products. An increased incidence of CRC was observed with frequent alcohol or meat consumption. No evidence of a protective effect for tea, coffee, garlic, fish and soy products was found. The level of evidence is moderate for aspirin, ß-carotene and selenium, but is low or very low for all other exposures or interventions.

Kosaki overgrowth syndrome: A novel pathogenic variant in PDGFRB and expansion of the phenotype including cerebrovascular complications.

Heterozygous activating variants in platelet-derived growth factor, beta (PDGFRB) are associated with phenotypes including Kosaki overgrowth syndrome (KOGS), Penttinen syndrome and infantile myofibromatosis (IM). Here, we present three new cases of KOGS, including a patient with a novel de novo variant c.1477A > T p.(Ser493Cys), and the oldest known individual age 53 years. The KOGS phenotype includes characteristic facial features, tall stature, scoliosis, hyperelastic thin skin, lipodystrophy, variable intellectual and neurological deterioration, and abnormalities on brain imaging. Long-term outcome is unknown. Our cases confirm the phenotypic spectrum includes progressive flexion contractures, camptodactyly, widely spaced teeth, and constriction rings. We also propose novel occasional features including craniosynostosis, ocular pterygia, anterior chamber cleavage syndrome, early osteoporosis, increased pigmentation, recurrent haematomas, predisposition to cellulitis, nail dystrophy, carpal tunnel syndrome, recurrent hypoglycaemia in infancy, joint dislocation, and splenomegaly. Importantly, we report fusiform aneurysm of the basilar artery in two patients. Complications include thrombosis and stroke in the oldest reported patient and fatal rupture at the age of 21 in the patient with the novel variant. We conclude that cerebrovascular complications are part of the phenotypic spectrum of KOGS and KOGS-like disorders and suggest vascular imaging is indicated in these patients.

Use of proton pump inhibitors in adults in France: a nationwide drug utilization study.

PURPOSE: Proton pump inhibitor (PPI) drugs are approved for the management of gastric acid-related diseases, mainly treatment of gastroesophageal reflux disease, treatment of nonsteroidal anti-inflammatory drugs (NSAID)-related gastrointestinal complications and prevention in at-risk patients, Helicobacter pylori eradication, and treatment of ulcers. PPIs are one of the most commonly prescribed drug class worldwide, and off-label use is widespread. The aim of this study was to describe outpatient PPI use of the whole adult population in France, based on the French National Health Data System (SNDS). METHODS: All individuals aged 18 years or older, with at least one dispensing for PPI between January 1, 2015 and December 31, 2015, were identified as PPI users. PPI users were considered as new users if they received no dispensing for PPI in the prior year. New users were followed until treatment discontinuation or up to 1 year, whichever occurred first. Characteristics of new users and of their PPI treatment were described, overall and separately by treatment indication. RESULTS: In total, 15,388,419 PPI users were identified in 2015 (57.0% women; mean age 57.0 years), accounting for 29.8% of the French adult population. Of them, 7,399,303 were new PPI users; mean treatment duration was 40.9 days, and 4.1% received a continuous PPI therapy lasting more than 6 months (10.2% among new users > 65 years versus 2.4% among those 18-65 years). For 53.5% of new users, indication for PPI therapy was a co-prescription with NSAID; in this indication, the large majority of patients (79.7%) had no measurable risk factor supporting a systematic prophylactic co-prescription of PPI. A proportion of 32.4% of new users did not have any identified comedication or inpatient diagnosis supporting an indication for PPI therapy; among them, only a small proportion (7.3% overall, and 8.4% of patients aged > 65 years) underwent a procedure investigating the digestive tract at the time of PPI initiation. CONCLUSION: The results of this study suggest PPI overuse in France, not always in line with the French guidelines. In particular, inappropriate co-prescription with NSAID was frequent. Efforts should be made to limit PPI treatment to appropriate indications and durations.

Management of Nonvariceal Upper Gastrointestinal Bleeding: Guideline Recommendations From the International Consensus Group.

Description: This update of the 2010 International Consensus Recommendations on the Management of Patients With Nonvariceal Upper Gastrointestinal Bleeding (UGIB) refines previous important statements and presents new clinically relevant recommendations. Methods: An international multidisciplinary group of experts developed the recommendations. Data sources included evidence summarized in previous recommendations, as well as systematic reviews and trials identified from a series of literature searches of several electronic bibliographic databases from inception to April 2018. Using an iterative process, group members formulated key questions. Two methodologists prepared evidence profiles and assessed quality (certainty) of evidence relevant to the key questions according to the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Group members reviewed the evidence profiles and, using a consensus process, voted on recommendations and determined the strength of recommendations as strong or conditional. Recommendations: Preendoscopic management: The group suggests using a Glasgow Blatchford score of 1 or less to identify patients at very low risk for rebleeding, who may not require hospitalization. In patients without cardiovascular disease, the suggested hemoglobin threshold for blood transfusion is less than 80 g/L, with a higher threshold for those with cardiovascular disease. Endoscopic management: The group suggests that patients with acute UGIB undergo endoscopy within 24 hours of presentation. Thermocoagulation and sclerosant injection are recommended, and clips are suggested, for endoscopic therapy in patients with high-risk stigmata. Use of TC-325 (hemostatic powder) was suggested as temporizing therapy, but not as sole treatment, in patients with actively bleeding ulcers. Pharmacologic management: The group recommends that patients with bleeding ulcers with high-risk stigmata who have had successful endoscopic therapy receive high-dose proton-pump inhibitor (PPI) therapy (intravenous loading dose followed by continuous infusion) for 3 days. For these high-risk patients, continued oral PPI therapy is suggested twice daily through 14 days, then once daily for a total duration that depends on the nature of the bleeding lesion. Secondary prophylaxis: The group suggests PPI therapy for patients with previous ulcer bleeding who require antiplatelet or anticoagulant therapy for cardiovascular prophylaxis.

Increasing incidence of colorectal cancer in young adults in Europe over the last 25 years.

OBJECTIVE: The incidence of colorectal cancer (CRC) declines among subjects aged 50 years and above. An opposite trend appears among younger adults. In Europe, data on CRC incidence among younger adults are lacking. We therefore aimed to analyse European trends in CRC incidence and mortality in subjects younger than 50 years. DESIGN: Data on age-related CRC incidence and mortality between 1990 and 2016 were retrieved from national and regional cancer registries. Trends were analysed by Joinpoint regression and expressed as annual percent change. RESULTS: We retrieved data on 143.7 million people aged 20-49 years from 20 European countries. Of them, 187 918 (0.13%) were diagnosed with CRC. On average, CRC incidence increased with 7.9% per year among subjects aged 20-29 years from 2004 to 2016. The increase in the age group of 30-39 years was 4.9% per year from 2005 to 2016, the increase in the age group of 40-49 years was 1.6% per year from 2004 to 2016. This increase started earliest in subjects aged 20-29 years, and 10-20 years later in those aged 30-39 and 40-49 years. This is consistent with an age-cohort phenomenon. Although in most European countries the CRC incidence had risen, some heterogeneity was found between countries. CRC mortality did not significantly change among the youngest adults, but decreased with 1.1%per year between 1990 and 2016 and 2.4% per year between 1990 and 2009 among those aged 30-39 years and 40-49 years, respectively. CONCLUSION: CRC incidence rises among young adults in Europe. The cause for this trend needs to be elucidated. Clinicians should be aware of this trend. If the trend continues, screening guidelines may need to be reconsidered.

Safety and efficacy of low-dose sirolimus in the PIK3CA-related overgrowth spectrum.

PURPOSE: PIK3CA-related overgrowth spectrum (PROS) encompasses a range of debilitating conditions defined by asymmetric overgrowth caused by mosaic activating PIK3CA variants. PIK3CA encodes the p110α catalytic subunit of phosphatidylinositol-3-kinase (PI3K), a critical transducer of growth factor signaling. As mTOR mediates the growth-promoting actions of PI3K, we hypothesized that the mTOR inhibitor sirolimus would slow pathological overgrowth. METHODS: Thirty-nine participants with PROS and progressive overgrowth were enrolled into open-label studies across three centers, and results were pooled. For the primary outcome, tissue volumes at affected and unaffected sites were measured by dual energy X-ray absorptiometry during 26 weeks of untreated run-in and 26 weeks of sirolimus therapy. RESULTS: Thirty participants completed the study. Sirolimus led to a change in mean percentage total tissue volume of -7.2% (SD 16.0, p = 0.04) at affected sites, but not at unaffected sites (+1.7%, SD 11.5, p = 0.48) (n = 23 evaluable). Twenty-eight of 39 (72%) participants had ≥1 adverse event related to sirolimus of which 37% were grade 3 or 4 in severity and 7/39 (18%) participants were withdrawn consequently. CONCLUSION: This study suggests that low-dose sirolimus can modestly reduce overgrowth, but cautions that the side-effect profile is significant, mandating individualized risk-benefit evaluations for sirolimus treatment in PROS.

Beta3 adrenergic receptor stimulation in human macrophages inhibits NADPHoxidase activity and induces catalase expression via PPARγ activation.

The beta3 adrenergic receptor (ß3-AR) stimulation plays a protective role against preterm labor by blocking myometrial contraction, cytokine production, remodeling and apoptosis. We previously demonstrated that macrophage-induced ROS production in the myometrium was a key element leading to the induction of all these labor-associated features. We thus aimed to investigate if the ß3-AR could be expressed in human macrophages and could trigger its protective role in the myometrium by directly inhibiting ROS production. Using lipopolysaccharide (LPS)-stimulated myometrial samples and cell co-culture experiments, we demonstrated that ß3-AR stimulation inhibits the activation of the NADPH oxidase, leading to the subsequent inhibition of ROS production by macrophages. This antioxidant effect was associated with a potent anti-inflammatory response in macrophages. Furthermore, we observed that ß3-AR leads to the expression of catalase not only in macrophages but also in myometrial cells, thereby preventing the transactivation of myometrial cells by hydrogen peroxide. Pharmacological experiments allowed us to demonstrate that these effects were driven by an Erk1/2-mediated activation of the antioxidant transcription factor PPARγ. These results suggest that ß3-AR protective effects in the myometrium could be due to its dual antioxidant properties. Further, the effects observed in a macrophage could highlight new applications in chronic inflammatory diseases.

Continuous Anti-TNFα Use Throughout Pregnancy: Possible Complications For the Mother But Not for the Fetus. A Retrospective Cohort on the French National Health Insurance Database (EVASION).

OBJECTIVES: Inflammatory bowel diseases (IBD) need long-term treatment, which can influence pregnancies in young women. Uncontrolled IBD is associated with poor pregnancy outcomes. Despite the labeling of Anti-tumor necrosis factor (TNF) antibodies (anti-TNFα) which indicates that their use is not recommended during pregnancy, anti-TNFα are increasingly being used during pregnancy and may expose women and their fetuses to treatment-related complications. Existing recommendations on the timing of treatment during pregnancy are inconsistent. We aimed to assess the safety of anti-TNFα treatment in pregnant women with IBD, and up to the first year of life for their children. METHODS: An exposed/non exposed retrospective cohort was conducted on the French national health system database SNIIRAM (Système National d'Information Inter-Régimes de l'Assurance Maladie). All IBD women who became pregnant between 2011 and 2014 were included. Women with concomitant diseases potentially treated with anti-TNFα were excluded. Anti-TNFα exposure (infliximab, adalimumab, golimumab or certolizumab pegol) during pregnancy was retrieved from the exhaustive prescription database in SNIIRAM. The main judgment criterion was a composite outcome of disease-, treatment- and pregnancy-related complications during pregnancy for the mother, and infections during the first year of life for children. RESULTS: We analyzed data from 11,275 pregnancies (8726 women with IBD), among which 1457 (12.9%) pregnancies were exposed to anti-TNFα, mainly infliximab or adalimumab, with 1313/7722 (17.0%) suffering from Crohn's disease and 144/3553 (4.1%) from ulcerative colitis. After adjusting for disease severity, steroid use, age, IBD type, and duration and concomitant 6-mercaptopurine use, anti-TNFα treatment was associated with a higher risk of overall maternal complications (adjusted Odds Ratio (aOR) = 1.49; 95% confidence interval (CI): 1.31-1.67) and infections (aOR = 1.31; 95% CI: 1.16-1.47). Maintaining anti-TNFα after 24 weeks did not increase the risk of maternal complication, but interrupting the anti-TNFα increased relapse risk. No increased risk for infection was found in children (aOR = 0.89; 95% CI: 0.76-1.05) born to mother exposed to anti-TNFα during pregnancy. CONCLUSIONS: Anti-TNFα treatment during pregnancy increased the risk of maternal complications compared to unexposed; however, discontinuation before week 24 increased the risk of disease flare. There was no increased risk for children exposed to anti-TNFα up to 1 year of life.

Glutathione prevents preterm parturition and fetal death by targeting macrophage-induced reactive oxygen species production in the myometrium.

Preterm birth is an inflammatory process resulting from the massive infiltration of innate immune cells and the production of proinflammatory cytokines in the myometrium. However, proinflammatory cytokines, which induce labor in vivo, fail to induce labor-associated features in human myometrial cells (MCs). We thus aimed to investigate if reactive oxygen species (ROS) production could be the missing step between immune cell activation and MC response. Indeed, we found that ROS production is increased in the human preterm laboring myometrium (27% ROS producing cells, respectively, versus 2% in nonlaboring controls), with 90% ROS production in macrophages. Using LPS-stimulated myometrial samples and cell coculture experiments, we demonstrated that ROS production is required for labor onset. Furthermore, we showed that ROS are required first in the NADPH oxidase (NADPHox)-2/NF-κB-dependent macrophage response to inflammatory stimuli but, more importantly, to trigger macrophage-induced MCs transactivation. Remarkably, in a murine model of LPS-induced preterm labor (inducing delivery within 17 hours, with no pup survival), cotreatment with glutathione delayed labor onset up to 94 hours and prevented in utero fetal distress, allowing 46% pups to survive. These results suggest that targeting ROS production with the macrophage-permeable antioxidant glutathione could constitute a promising strategy to prevent preterm birth.

First nationwide web-based surveillance system for influenza-like illness in pregnant women: participation and representativeness of the French G-GrippeNet cohort.

BACKGROUND: Pregnancy is a risk factor for severe influenza resulting in increased risks of hospitalisation and death in mothers and their new-borns. Our objective was to assess the representativeness and participation of French women to a new web-based collaborative tool for data collection and monitoring of Influenza Like Illness (ILI) during pregnancy. METHODS: During the 2014/2015 influenza season, pregnant women living in metropolitan France were enrolled through a web platform ( https://www.grippenet.fr/). Then throughout the season, participants were asked to report, on a weekly basis, if they had experienced symptoms of ILI. Representativeness was assessed by comparing the characteristics of participants to those of the French National Perinatal Survey. For each participant, the participation rate was the number of weekly questionnaires completed, divided by the length of follow-up (in weeks). Predictors of active participation (participation rate >15%) were assessed by multivariate logistic regression. RESULTS: A total of 153 women were enrolled. Participants were older (mean age 34 years vs. 29 years) and more highly educated (high school level 89% versus 52%) than the general population of pregnant women in France, but the sample did not differ on pregnancy-related characteristics (parity, history of hospitalisation during a previous pregnancy). The median rate of participation was high (78%, interquartile range: 34-96). Higher educational level and participation to a previous GrippeNet.fr season were associated with active participation. CONCLUSION: Despite small sample size and lack of representativeness, the retention rate was high, suggesting that pregnant women are prone to adhere to a longitudinal follow-up of their health status via the Internet.

Biphasic Erk1/2 activation sequentially involving Gs and Gi signaling is required in beta3-adrenergic receptor-induced primary smooth muscle cell proliferation.

The beta3 adrenergic receptor (B3-AR) reportedly induces cell proliferation, but the signaling pathways that were proposed, involving either Gs or Gi coupling, remain controversial. To further investigate the role of G protein coupling in B3-AR induced proliferation, we stimulated primary human myometrial smooth muscle cells with SAR150640 (B3-AR agonist) in the absence or presence of variable G-protein inhibitors. Specific B3-AR stimulation led to an Erk1/2 induced proliferation. We observed that the proliferative effects of B3-AR require two Erk1/2 activation peaks (the first after 3min, the second at 8h). Erk1/2 activation at 3min was mimicked by forskolin (adenylyl-cyclase activator), and was resistant to pertussis toxin (Gi inhibitor), suggesting a Gs protein signaling. This first signaling also required the downstream Gs signaling effectors PKA and Src. However, Erk1/2 activation at 8h turned out to be pertussis toxin-dependent, and PKA-independent, indicating a Gi signaling pathway in which Src and PI3K were required. The pharmacological inhibition of both the Gs and Gi pathway abolished B3-AR-induced proliferation. Altogether, these data indicate that B3-AR-induced proliferation depends on the biphasic activation of Erk1/2 sequentially induced by the Gs/PKA/Src and Gi/Src/PI3K signaling pathways.