In Vitro Tests for a Rapid Evaluation of Antidiabetic Potential of Plant Species Containing Caffeic Acid Derivatives: A Validation by Two Well-Known Antidiabetic Plants, Ocimum gratissimum L. Leaf and Musanga cecropioides R. Br. ex Tedlie (Mu) Stem Bark

Plant bioactive extracts represent a major resource for identifying drugs and adjuvant therapy for type 2 diabetes. To promote early screening of plants’ antidiabetic potential, we designed a four in vitro tests strategy to anticipate in vivo bioactivity. Two antidiabetic plants were studied: Ocimum gratissimum L. (Oc) leaf extract and Musanga cecropoides R. Br. ex Tedlie (Mu) stem bark extract. Chemical compositions were analyzed by LCMS and HPLC. Antidiabetic properties were measured based on (1) INS-1 cells for insulin secretion, (2) L6 myoblast cells for insulin sensitization (Glut-4 translocation), (3) L6 myoblast cells for protection against hydrogen peroxide (H₂O₂) oxidative stress (cell mortality), and (4) liver microsomial fraction for glucose-6-phosphastase activity (G6P). Oc extract increased insulin secretion and insulin sensitivity, whereas it decreased oxidative stress-induced cell mortality and G6P activity. Mu extract decreased insulin secretion and had no effect on insulin sensitivity or G6P activity, but it increased oxidative stress-induced cell mortality. Results were compared with NCRAE, an antidiabetic plant extract used as reference, previously characterized and reported with increased insulin secretion and insulin sensitivity, protection against oxidative stress, and decreased G6P activity. The proposed set of four in vitro tests combined with chemical analysis provided insight into the interest in rapid early screening of plant extract antidiabetic potential to anticipate pharmaco-toxicological in vivo effects.

Increase in insulin sensitivity by the association of chicoric acid and chlorogenic acid contained in a natural chicoric acid extract (NCRAE) of chicory (Cichorium intybus L.) for an antidiabetic effect

ETHNOPHARMACOLOGICAL RELEVANCE

Chicory (Cichorium intybus L.) is an indigenous vegetable widely cultivated in Europe, America and Asia. In ancient times, the leaves, flowers, seeds, and roots have been used as a wealth of health benefits including its tonic effects, the ability to ease digestive problems and to detoxify liver. In Indian traditional therapy, chicory was known to possess antidiabetic effect. In the traditional medicine of Bulgaria and Italy, chicory was used as hypoglycemic decoctions.

AIMS OF THE STUDIES

We wanted to obtain the complete chemical composition of the natural chicoric acid extract (NCRAE), a chicory root extract rich in chicoric acid, which previously showed its glucose tolerance effect in normal rats. To investigate if the whole NCRAE is required to be effective, we performed a comparative in vivo experiment on STZ diabetic rats treated either with NCRAE or a mixture composed of the two major compounds of NCRAE.

MATERIALS AND METHODS

LC-MS method has been used to analyze the exhaustive composition of NCRAE: we have determined that chicoric acid and chlorogenic acid represented 83.8% of NCRAE. So, we have prepared a solution mixture of chicoric acid and chlorogenic acid named SCCAM, in order to compare in vivo the antidiabetic effects of this last and NCRAE in streptozotocin diabetic rats. In vitro experiments were performed on L6 cell line both for glucose uptake and for the protective effect against H2O2 oxidative stress. Also, we have evaluated DPPH and ORAC (Oxygen Radical Absorbance Capacity) antioxidative capacities of the two compositions.

RESULTS

The LC-MS analysis confirmed the high abundance of chicoric acid (64.2%) in NCRAE and a second part of NCRAE is composed of caffeoylquinic acids (CQAs) at 19.6% with among them the chlorogenic acid. This result has permitted us to prepare a mixture of synthetic L-chicoric acid (70%) and synthetic chlorogenic acid (30%): the solution is designated SCCAM. Our results showed that both NCRAE and SCCAM are able to improve a glucose tolerance in STZ diabetic rats after a subchronic administration of seven days. Alone NCRAE allows to significantly decrease the basal hyperglycemia after six days of treatment. To explain these difference of effects between NCRAE and SCCAM, we have compared their in vitro effects on the L6 muscle cell line both for the insulin sensitizing effect and for their protective action in pretreatment against H2O2. We have also compared their antioxidant capacities. In conclusion, we demonstrated that NCRAE, a natural extract of chicory (Cichorium intybus) rich in CRA and CQAs improves glucose tolerance and reduces the basal hyperglycemia in STZ diabetic rats.

Metrics and textural features of MRI diffusion to improve classification of pediatric posterior fossa tumors

BACKGROUND AND PURPOSE

Qualitative radiologic MR imaging review affords limited differentiation among types of pediatric posterior fossa brain tumors and cannot detect histologic or molecular subtypes, which could help to stratify treatment. This study aimed to improve current posterior fossa discrimination of histologic tumor type by using support vector machine classifiers on quantitative MR imaging features.

MATERIALS AND METHODS

This retrospective study included preoperative MRI in 40 children with posterior fossa tumors (17 medulloblastomas, 16 pilocytic astrocytomas, and 7 ependymomas). Shape, histogram, and textural features were computed from contrast-enhanced T2WI and T1WI and diffusivity (ADC) maps. Combinations of features were used to train tumor-type-specific classifiers for medulloblastoma, pilocytic astrocytoma, and ependymoma types in separation and as a joint posterior fossa classifier. A tumor-subtype classifier was also produced for classic medulloblastoma. The performance of different classifiers was assessed and compared by using randomly selected subsets of training and test data.

RESULTS

ADC histogram features (25th and 75th percentiles and skewness) yielded the best classification of tumor type (on average >95.8% of medulloblastomas, >96.9% of pilocytic astrocytomas, and >94.3% of ependymomas by using 8 training samples). The resulting joint posterior fossa classifier correctly assigned >91.4% of the posterior fossa tumors. For subtype classification, 89.4% of classic medulloblastomas were correctly classified on the basis of ADC texture features extracted from the Gray-Level Co-Occurence Matrix.

CONCLUSIONS

Support vector machine-based classifiers using ADC histogram features yielded very good discrimination among pediatric posterior fossa tumor types, and ADC textural features show promise for further subtype discrimination. These findings suggest an added diagnostic value of quantitative feature analysis of diffusion MR imaging in pediatric neuro-oncology.

Serial determinations of serum CEA in monitoring management of patients with colorectal carcinoma

Serum concentrations were determined serially in two groups of patients with colorectal carcinoma: in 123 after curative resection and in 34 with residual cancer. Of the first group, in 98 serum CEA fluctuated within the normal range or with a 2-fold larger amplitude evidencing effective surgery because only 9 had recurrence; in 25 serum CEA rose persistently from a postoperative nadir indicating relapse, mostly liver metastases. Of the 34 patients with relapse, 3 had clinically and 7 CEA-directed second-look laparotomy; although 7 had operation with curative intent, only 3 remained disease-free. In the second group, there were 26 patients after palliative surgery and 8 during nonsurgical treatment. Serum CEA fluctuated within the normal range in 2 patients in remission and in 3 with progressive cancer, and rose in parallel to cancer progression in 29. Thus, serum CEA within or slightly above the normal range was 88% predictive that the patient might be free of disease or in remission; whereas elevated or rising level indicated disease progression. Accordance between serum CEA and clinical status occurred in 145 of 157 (92%) patients.