“Herbal incense”: Designer drug blends as cannabimimetics and their assessment by drug discrimination and other in vivo bioassays

Recently, synthetic cannabinoids originally designed for testing in the laboratory only have found use recreationally in designer herbal blends, originally called “Spice”. The myriad of compounds found are for the most part potent full agonists of the cannabinoid receptor 1, producing effects similar to tetrahydrocannabinol (THC) and marijuana. Drug discrimination of these compounds offers a specific behavioral test that can help determine whether these new synthetic compounds share a similar “subjective high” with the effects of marijuana/THC. By utilization of drug discrimination and other behavioral techniques, a better understanding of these new “designer” cannabinoids may be reached to assist in treating both the acute and chronic effects of these drugs. The paper provides a brief exposé of modern cannabinoid research as a backdrop to the recreational use of designer herbal blend cannabimimetics.     

Moving around the molecule: Relationship between chemical structure and in vivo activity of synthetic cannabinoids

Originally synthesized for research purposes, indole- and pyrrole-derived synthetic cannabinoids are the most common psychoactive compounds contained in abused products marketed as “spice” or “herbal incense.” While CB₁ and CB₂ receptor affinities are available for most of these research chemicals, in vivo pharmacological data are sparse. In mice, cannabinoids produce a characteristic profile of dose-dependent effects: antinociception, hypothermia, catalepsy and suppression of locomotion. In combination with receptor binding data, this tetrad battery has been useful in evaluation of the relationship between the structural features of synthetic cannabinoids and their in vivo cannabimimetic activity. Here, published tetrad studies are reviewed and additional in vivo data on synthetic cannabinoids are presented. Overall, the best predictor of likely cannabimimetic effects in the tetrad tests was good CB₁ receptor affinity. Further, retention of good CB₁ affinity and in vivo activity was observed across a wide array of structural manipulations of substituents of the prototypic aminoalkylindole molecule WIN55,212-2, including substitution of an alkyl for the morpholino group, replacement of an indole core with a pyrrole or phenylpyrrole, substitution of a phenylacetyl or tetramethylcyclopropyl group for JWH-018's naphthoyl, and halogenation of the naphthoyl group. This flexibility of cannabinoid ligand–receptor interactions has been a particular challenge for forensic scientists who have struggled to identify and regulate each new compound as it has appeared on the drug market. One of the most pressing future research needs is determination of the extent to which the pharmacology of these synthetic cannabinoids may differ from those of classical cannabinoids.     

Distinct pharmacology and metabolism of K2 synthetic cannabinoids compared to Δ-THC: Mechanism underlying greater toxicity?

K2 or Spice products are emerging drugs of abuse that contain synthetic cannabinoids (SCBs). Although assumed by many teens and first time drug users to be a “safe” and “legal” alternative to marijuana, many recent reports indicate that SCBs present in K2 produce toxicity not associated with the primary psychoactive component of marijuana, ?⁹-tetrahydrocannabinol (Δ⁹-THC). This mini-review will summarize recent evidence that use of K2 products poses greater health risks relative to marijuana, and suggest that distinct pharmacological properties and metabolism of SCBs relative to Δ⁹-THC may contribute to the observed toxicity. Studies reviewed will indicate that in contrast to partial agonist properties of Δ⁹-THC typically observed in vitro, SCBs in K2 products act as full cannabinoid receptor type 1 (CB1R) and type 2 (CB2R) agonists in both cellular assays and animal studies. Furthermore, unlike Δ⁹-THC metabolism, several SCB metabolites retain high affinity for, and exhibit a range of intrinsic activities at, CB1 and CB2Rs. Finally, several reports indicate that although quasi-legal SCBs initially evaded detection and legal consequences, these presumed “advantages” have been limited by new legislation and development of product and human testing capabilities. Collectively, evidence reported in this mini-review suggests that K2 products are neither safe nor legal alternatives to marijuana. Instead, enhanced toxicity of K2 products relative to marijuana, perhaps resulting from the combined actions of a complex mixture of different SCBs present and their active metabolites that retain high affinity for CB1 and CB2Rs, highlights the inherent danger that may accompany use of these substances.     

Behavioral pharmacology of designer cathinones: A review of the preclinical literature

“Bath salts” is one street name for a family of synthetic cathinones that display pharmacological effects resembling cocaine and commonly abused amphetamines. Despite extensive legislation aimed at the criminalization of bath salts, several designer cathinones are gaining a foothold in the illicit drug scene; for example, in the United Kingdom, mephedrone (4-methylmethcathinone, MEPH) is highly popular among drug abusers whereas, in the United States, MDPV (methylenedioxypyrovalerone) and methylone are highly prevalent. To date, knowledge about the hazards of designer cathinones is based mostly on hospital reports and anecdotal evidence derived from online surveys. Despite the paucity of preclinical studies directed toward designer cathinones, a number of invaluable findings arising from those studies are enabling scientists to develop their neuropharmacological profiles. Despite their commonalities in chemical structures, synthetic cathinones possess distinct neuropharmacological profiles and produce different behavioral effects, including unique effects on locomotor activity, learning, anxiety, thermoregulation, and abuse liability. The present review will discuss the behavioral effects of MEPH, MDPV, and methylone and compare those effects to established psychostimulant drugs. The rise in the use of designer cathinones in the United States and abroad justifies further investigations into these compounds, both for a greater understanding of the danger that “bath salts” pose to the public, and to provide insight into replacement cathinones as they emerge onto the market.     

La symbolique des gravures rupestres du Mont Bego

The analysis of imaginary anthropological structures elaborated by Gilbert Durand enables us to identify a symbolic language of ideograms from Mont Bego (circa 2500-1800 BC). There are three main types of figures: figures associated with the Bull- God and with the God of Storms, which come under the first function “heroic”; figures depicting harnessing and reticulates which evoke ploughed fields ands make reference to the feminine and maternal function known as “mystic nocturne”; figures linked to initiation, to the relationship between the first and the second function, which come under the function known as “synthetic nocturne”. These figures are located particularlyon the slab known as the “witch”. A comparative study of the later symbolic figures, presented in worship practises in archaic and then classic Greece and in the Greek-Roman imaginary, helps us to understand that Mediterranean mankind portrays a coherent image of the cosmos. This image is stable from the proto-Ligurian figures of Mont Bego until the forms elaborated by the Greek-Roman religious imaginary, in particular through mysterious rituals.     

Pharmacological and nutritional agents promoting browning of white adipose tissue

The role of brown adipose tissue in the regulation of energy balance and maintenance of body weight is well known in rodents. Recently, interest in this tissue has re-emerged due to the realization of active brown-like adipose tissue in adult humans and inducible brown-like adipocytes in white adipose tissue depots in response to appropriate stimuli (“browning process”). Brown-like adipocytes that appear in white fat depots have been called “brite” (from brown-in-white) or “beige” adipocytes and have characteristics similar to brown adipocytes, in particular the capacity for uncoupled respiration. There is controversy as to the origin of these brite/beige adipocytes, but regardless of this, induction of the browning of white fat represents an attractive potential strategy for the management and treatment of obesity and related complications. Here, the different physiological, pharmacological and dietary determinants that have been linked to white-to-brown fat remodeling and the molecular mechanisms involved are reviewed in detail. In the light of available data, interesting therapeutic perspectives can be expected from the use of specific drugs or food compounds able to induce a program of brown fat differentiation including uncoupling protein 1 expression and enhancing oxidative metabolism in white adipose cells. However, additional research is needed, mainly focused on the physiological relevance of browning and its dietary control, where the use of ferrets and other non-rodent animal models with a more similar adipose tissue organization and metabolism to humans could be of much help. This article is part of a Special Issue entitled Brown and White Fat: From Signaling to Disease.     

Synthetic cannabinoids: Analysis and metabolites

Cannabimimetics (commonly referred to as synthetic cannabinoids), a group of compounds encompassing a wide range of chemical structures, have been developed by scientists with the hope of achieving selectivity toward one or the other of the cannabinoid receptors CB1 and CB2. The goal was to have compounds that could possess high therapeutic activity without many side effects. However, underground laboratories have used the information generated by the scientific community to develop these compounds for illicit use as marijuana substitutes. This chapter reviews the different classes of these “synthetic cannabinoids” with particular emphasis on the methods used for their identification in the herbal products with which they are mixed and identification of their metabolites in biological specimens.     

Living in a dangerous world decreases maternal care: a study in serotonin transporter knockout mice

Adverse early experiences can profoundly influence the adult behavioral profile. When pregnant and lactating mice are confronted with soiled bedding of unfamiliar males (UMB), these stimuli signal the danger of infanticide and thus simulate a “dangerous world”. In a previous study, offspring of UMB treated mothers were shown to display increased anxiety-like behavior and reduced exploratory locomotion as adults, compared to mice treated with neutral bedding (NB, “safe environment”). The aim of this study was to elucidate the mechanisms conveying these effects of living in a “dangerous world” to offspring behavior. We hypothesized the mother to be the major link and focused on the influence of UMB on maternal stress hormones and behavior. Thus, we investigated fecal corticosterone metabolites (CM) and maternal care of pregnant and lactating mice either treated with NB or UMB. The offspring were subsequently tested for their anxiety-like and exploratory behavior. Mothers treated with UMB showed a significantly higher increase of fecal CM following the initial treatment, than NB treated mothers, indicating that the odor cues of potentially infanticidal males represented an ethologically relevant stimulus. Whereas the hormonal stress response habituated, living in a “dangerous world” led to a distinct and consistent reduction of maternal care behavior, particularly concerning the duration of licking and grooming the pups. Surprisingly, we could not confirm our former findings of altered phenotypes in the offspring of UMB treated mothers. In summary, we hypothesize that the frequently described effects of early life adversity on the offspring's behavioral profile are mediated primarily by maternal care in altricial rodents.     

Thermal environment and human birth weight

Human birth weight is known to be influenced by several factors, including maternal energy supply, maternal stature, disease status, smoking status and gestation length. This article proposes that the thermal environment may be a further factor influencing birth weight. Experimental animal studies demonstrate clear effects of thermal stress on placental function and birth weight, but may have limited relevance for humans due to between-species differences in pregnancy physiology. Observational studies suggest an inverse relationship between environmental temperature and birth weight within and between human populations. Variation in maternal size, body fatness, pregnancy weight gain and heat production is predicted to influence maternal thermoregulatory capacity, as are the size and composition of the foetus. These associations generate the hypothesis that low birth weight in hot environments may in part represent an adaptation to environmental heat stress.     

α-Actinin-4-Mediated FSGS: An Inherited Kidney Disease Caused by an Aggregated and Rapidly Degraded Cytoskeletal Protein

Focal segmental glomerulosclerosis (FSGS) is a common pattern of renal injury, seen as both a primary disorder and as a consequence of underlying insults such as diabetes, HIV infection, and hypertension. Point mutations in theα-actinin-4 gene ACTN4 cause an autosomal dominant form of human FSGS. We characterized the biological effect of these mutations by biochemical assays, cell-based studies, and the development of a new mouse model. We found that a fraction of the mutant protein forms large aggregates with a high sedimentation coefficient. Localization of mutant α-actinin-4 in transfected and injected cells, as well as in situ glomeruli, showed aggregates of the mutant protein. Video microscopy showed the mutant α-actinin-4 to be markedly less dynamic than the wild-type protein. We developed a “knockin” mouse model by replacing Actn4 with a copy of the gene bearing an FSGS-associated point mutation. We used cells from these mice to show increased degradation of mutant α-actinin-4, mediated, at least in part, by the ubiquitin–proteasome pathway. We correlate these findings with studies of α-actinin-4 expression in human samples. “Knockin” mice with a disease-associated Actn4 mutation develop a phenotype similar to that observed in humans. Comparison of the phenotype in wild-type, heterozygous, and homozygous Actn4 “knockin” and “knockout” mice, together with our in vitro data, suggests that the phenotypes in mice and humans involve both gain-of-function and loss-of-function mechanisms.     

Extra-embryonic-specific imprinted expression is restricted to defined lineages in the post-implantation embryo

A subset of imprinted genes in the mouse have been reported to show imprinted expression that is restricted to the placenta, a short-lived extra-embryonic organ. Notably, these so-called “placental-specific” imprinted genes are expressed from both parental alleles in embryo and adult tissues. The placenta is an embryonic-derived organ that is closely associated with maternal tissue, and as a consequence, maternal contamination can be mistaken for maternal-specific imprinted expression. The complexity of the placenta, which arises from multiple embryonic lineages, poses additional problems in accurately assessing allele-specific repressive epigenetic modifications in genes that also show lineage-specific silencing in this organ. These problems require that extra evidence be obtained to support the imprinted status of genes whose imprinted expression is restricted to the placenta. We show here that the extra-embryonic visceral yolk sac (VYS), a nutritive membrane surrounding the developing embryo, shows a similar “extra-embryonic–lineage-specific” pattern of imprinted expression. We present an improved enzymatic technique for separating the bilaminar VYS and show that this pattern of imprinted expression is restricted to the endoderm layer. Finally, we show that VYS “extra-embryonic–lineage-specific” imprinted expression is regulated by DNA methylation in a similar manner as shown for genes showing multi-lineage imprinted expression in extra-embryonic, embryonic, and adult tissues. These results show that the VYS is an improved model for studying the epigenetic mechanisms regulating extra-embryonic–lineage-specific imprinted expression.     

The newborn rat's stress system readily habituates to repeated and prolonged maternal separation, while continuing to respond to stressors in context dependent fashion

Adrenal corticosterone secretion of newborn mice rapidly desensitizes to repeated maternal absence. The present study investigated the effects of novelty exposure, maternal care and genotype on this phenomenon.Maternal separation (MS) took place on postnatal days (pnd) 3-5. In Wistar rats, the degree of novelty in the MS-environment was varied by exposing pups to: (i) “home separation”: pups remained in the home cage; (ii) “novel separation”: pups were placed individually in a novel cage. Maternal care was recorded on pnd 1 to 4. To investigate the effect of genotype, we also examined Long Evans in the “home separation” condition. Basal and stress-induced ACTH and corticosterone levels were measured. Adrenal tyrosine hydroxylase (TH) and melanocortin receptor-2 (MCR-2) proteins served as markers for adrenal function.We show, in both rat strains, that the rise in plasma corticosterone induced by a single 8 h-MS on pnd 5 was abolished, when this separation procedure had also been performed on pnd 3 and 4. Habituation to maternal absence occurred irrespective of housing conditions. However, pups in the “home separation” condition received less maternal care upon reunion than those placed in the “novel separation”. These “home separation” pups appeared more responsive to a subsequent acute novelty-stressor, and their adrenal TH and MCR-2 were higher. Long Evans rats appeared more stress responsive than the Wistars, in the home separation condition.In conclusion, separation environment, maternal care and genotype do not affect adrenal desensitization to repeated 8 h-MS itself, but may modulate the adrenal stress-responsiveness of separated pups.     

Is there an embryopathy associated with first-trimester exposure to angiotensin-converting enzyme inhibitors and angiotensin receptor antagonists? A critical review of the evidence

Drugs that interfere with the renin-angiotensin system, such as angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), are widely used to manage hypertension and heart failure. Adequate functioning of the RAS is essential for normal fetal kidney development. The potential for ACEIs and ARBs to impair fetal and neonatal renal function if taken after the first trimester of pregnancy has been well documented. Although these drugs were not found to be teratogenic in animals, until recently little was known about the teratogenic effects of ACEIs and ARBs in humans when exposure was limited to the first trimester of pregnancy. New evidence from epidemiologic studies indicates that there may be an elevated teratogenic risk when these drugs are taken during the first trimester of pregnancy. However, this elevated risk does not appear to be specific to ACEIs and ARBs, but is instead related to maternal factors and diseases that typically coexist with hypertension in pregnancy, such as diabetes, advanced maternal age, and obesity. Women who become pregnant while being treated with an ACEI or ARB should be advised to avoid exposure to these drugs during the second and third trimesters of pregnancy by switching to a different class of antihypertensive drugs between weeks 8 and 10 after conception. Birth Defects Research (Part A) 94:576-598, 2012. ? 2012 Wiley Periodicals, Inc.     

Endocannabinoid signaling in synchronizing embryo development and uterine receptivity for implantation

There are reports of adverse effects of cannabinoids on pregnancy outcome including retarded embryo development and pregnancy failure. Thus, discoveries of endogenous cannabinoid-like lipid mediators and cannabinoid receptors raise questions about their pathophysiological roles during normal pregnancy. We previously reported that anandamide, an endogenously produced arachidonate derivative (endocannabinoid), is synthesized in the female reproductive tracts, and it acts on cannabinoid receptors expressed on the cell surface of the embryo to regulate the preimplantation embryo development and implantation in mice. This review presents genetic, molecular, physiological and pharmacological evidence that the levels of uterine anandamide and blastocyst CB1 cannabinoid receptors are coordinately regulated to synchronize preimplantation development and uterine receptivity for implantation in mice.     

Embryonic resorption in context to intragestational corpus luteum regression: A longitudinal ultrasonographic study in the European brown hare (Lepus europaeus PALLAS, 1778)

Embryonic resorption is frequently observed in polytocous mammals. Often it occurs as partial litter resorption affecting only single conceptuses of a whole litter. The aim of the study was to describe the incidence and morphology of embryonic resorption in the European brown hare (Lepus europaeus). In 154 pregnancies viable conceptuses, conceptuses undergoing resorption and CL of pregnancy were ultrasonographically monitored during the entire gestation period. Resorptions were classified into (1) “pre-implantation resorptions,” (2) “peri-implantation resorptions,” and (3) “post-implantation resorptions.” The incidence of resorption in the pre-implantation period was 9%, in the peri-implantation period 9%, and in the post-implantation period 24%. Post-implantation resorptions were found up to late pregnancy stages when fetal development was already in progress. The highest daily incidence of resorption was on Day 8 of the 42-day pregnancy. In 91% of the cases, the regression of one CL was observed, while an embryo was undergoing resorption at the same time. The number of resorptions did not significantly differ from the number of CL in regression during gestation, suggesting an interesting one-resorption-to-one-regression relationship. The ultrasonographic appearance of the luteal regression during pregnancy was similar to the morphology characteristic for postpartal luteolysis.     

Le « nucléus Donggutuo » et sa signification dans l’industrie du paléolithique inférieur de Donggutuo, bassin de Nihewan, Chine du Nord

As one of the most important Lower Pleistocene sites of the Nihewan basin in North China, Donggutuo (DGT) site is well known for its fine retouched small tools and characters of flake industry. However, new excavations still reveal some new discoveries and educe some new issues to us. For example, the “DGT core” introduced in this article is a new discovered typotechnology and indicates new economic strategy of the local people, which was never known before in this area at the time of 1.1 Ma B.P. The paper provides general background and statistic analysis of DGT industry including special method applied to the “DGT core” and discusses possible influence of environmental change for the emerging of the “DGT core”. The “DGT core” shows a germinated microlithic tradition and reflects a cultural diversity of early humans in the Lower Paleolithic in North China.     

Modern human origins: continuity, replacement, and masticatory robusticity in Australasia

Morphological evidence for a Multiregional (MR) model of human origins is suggested by a series of “linking traits” seen in the crania of late Javanese Homo erectus from Ngandong and anatomically modern Australian crania. A few studies that consider the genetic, structural, or functional aspects of these regional traits suggest their appearance is heavily influenced not by shared phylogeny but by a common “strong” masticatory pattern. Using dental occlusal areas, external mandibular metrics, internal biomechanical properties of the mandibular corpus measured from CT scans, and nonmetric traits associated with the attachment of masticatory muscles, we test the hypothesis that Australians exhibit evidence of a “strong” masticatory pattern. We use a mixed-sex comparative human sample (n = 415) that includes precontact Alaskans from Point Hope and the Aleutian Islands, Californians, Peruvians, an urban forensic sample, and the late Pleistocene Afalou-Taforalt sample. In comparison with recent humans known to exhibit such patterns, Australian mandibles show none of the expected changes related to producing and dissipating heavy occlusal loads. This is true regardless of whether external or internal mandibular dimensions are considered, albeit Australians show large occlusal areas and relatively large section modulus indices. Thus, a prime functional argument proposed for the origin of some Australian regional features is not supported by these data.     

COVID-19 in pregnancy: What we know from the first year of the pandemic

The COVID-19 pandemic has infected nearly 178 million people and claimed the lives of over 3.8 million in less than 15 months. This has prompted a flurry of research studies into the mechanisms and effects of SARS-CoV-2 viral infection in humans. However, studies examining the effects of COVID-19 in pregnant women, their placentae and their babies remain limited. Furthermore, reports of safety and efficacy of vaccines for SARS-CoV-2 in pregnancy are limited.This review concisely summarises the case studies and research on COVID-19 in pregnancy, to date. It also reviews the mechanism of infection with SARS-CoV-2, and its reliance and effects upon the renin-angiotensin-aldosterone system. Overall, the data suggest that infection during pregnancy can be dangerous at any time, but this risk to both the mother and fetus, as well as placental damage, increases during the third trimester. The possibility of vertical transmission, which is explored in this review, remains contentious. However, maternal infection with SARS-CoV-2 can increase risk of miscarriage, preterm birth and stillbirth, which is likely due to damage to the placenta.     

Dechorionation as a tool to improve the fish embryo toxicity test (FET) with the zebrafish (Danio rerio)

Prior to hatching, the zebrafish embryo is surrounded by an acellular envelope, the chorion. Despite repeated speculations, it could not be clarified unequivocally whether the chorion represents an effective barrier and, thus, protects the embryo from exposure to distinct chemicals. Potentially, there is a risk of generating false negative results in developmental toxicity studies due to limited permeability of the chorion for some compounds. The simplest way to exclude this is to remove the chorion and expose the “naked” embryo. In the context of ecotoxicity testing, standardized protocols do not exist for fish embryo dechorionation, and survival rates of dechorionated embryos have usually not been subjected to statistical analysis. Since reproducibly high survival rates are of fundamental importance for chemical toxicity assessment, the present study was designed to develop and optimize a dechorionation procedure. With appropriate modifications of the fish embryo test protocol, embryos can be dechorionated at 24 h post-fertilization (hpf) with survival rates of ≥ 90%. However, for fish embryo tests with dechorionated embryos, the standard positive control test substance, 3,4-dichloroaniline, should be replaced by another compound, e.g., acetone, since 3,4-dichloroaniline exerts its effects during the first 24 h of development. Dechorionation of younger stages (< 24 hpf) is generally possible, however with lower survival rates. The effect of dechorionation was demonstrated with the cationic polymer Luviquat HM 552, which is blocked by the chorion non-dechorionated embryos due to its molecular weight of ~ 400,000 Dalton, but becomes strongly toxic after dechorionation.