  In this paper we present new versions of the classical Brunn-Minkowski
inequality for different classes of measures and sets. We show that the
inequality \[
  \mu(\lambda A + (1-\lambda)B)^{1/n} \geq \lambda \mu(A)^{1/n} +
(1-\lambda)\mu(B)^{1/n} \] holds true for an unconditional product measure
$\mu$ with decreasing density and a pair of unconditional convex bodies $A,B
\subset \mathbb{R}^n$. We also show that the above inequality is true for any
unconditional $\log$-concave measure $\mu$ and unconditional convex bodies $A,B
\subset \mathbb{R}^n$. Finally, we prove that the inequality is true for a
symmetric $\log$-concave measure $\mu$ and a pair of symmetric convex sets $A,B
\subset \mathbb{R}^2$, which, in particular, settles two-dimensional case of
the conjecture for Gaussian measure proposed by R. Gardner and the fourth named
author.
  In addition, we deduce the $1/n$-concavity of the parallel volume $t \mapsto
\mu(A+tB)$, Brunn's type theorem and certain analogues of Minkowski first
inequality.
